Pulmonary cryptococcosis: A review of pathobiology and clinical aspects

Pulmonary cryptococcosis in immunocompetent children presenting with chest pain: Three case reports

BACKGROUND

Cryptococcus is a systemic opportunistic pathogenic fungus that can cause infections in both immunocompromised and immunocompetent hosts, with diverse clinical manifestations, ranging from asymptomatic pulmonary lesions to disseminated central nervous system infections. The incidence of pulmonary cryptococcosis (PC) has rapidly increased in recent years, with an increasing proportion of non-human immunodeficiency virus-infected and immunocompetent patients making its diagnosis challenging. If not properly recognized, PC can lead to systemic dissemination and high mortality rates. Early diagnosis and treatment can improve the prognosis. This study summarizes the clinical features of three immunocompetent children with PC who presented with chest pain to raise clinicians' awareness of the disease and reduce mortality.

CASE SUMMARY

Three male pediatric patients in good health were hospitalized because of chest pain without cough or fever. Chest computed tomography (CT) revealed pleural-based nodules and consolidation with cavitation. A lung biopsy was performed in one case, and Cryptococcus was cultured from the pathological tissues. Cryptococcus was detected in the alveolar lavage fluid, and serum Cryptococcus capsular(C. capsular) polysaccharide antigen was positive in one case, and the other case was positive for serum C. capsular polysaccharide. All patients received oral fluconazole treatment. Follow-up chest CT scans after six months showed significant resolution of the lesions.

CONCLUSION

PC can also occur in immunocompetent children. When encountering children with chest pain only in the clinic, one should be vigilant about PC, promptly complete the relevant examinations, and avoid misdiagnosis.

A fatal case of pulmonary cryptococcosis in an apparently immunocompetent patient from Cote D' Ivoire

Cryptococcosis is an opportunistic mycosis caused by Cryptococcus, mainly affecting the immunocompromised. We report a case of pulmonary cryptococcosis within a 31-year-old immunocompetent patient admitted for painful chest swelling evolving for 4 months prior to admission. The chest X-Ray showed a rounded pulmonary opacity. The chest ultrasound revealed a pulmonary abscess diffusing under the skin. Direct examination using the Indian ink and the May-Grunwald Giemsa staining revealed encapsulated yeasts in the pus. The Culture of the pus on the Sabouraud medium with chloramphenicol confirmed the presence of Cryptococcus neoformans. Cryptococcal antigen was positive. This case reminds us that cryptococcosis should be considered even without immunosuppression.

Cryptococcosis

Cryptococcosis is an invasive fungal infection caused by yeasts of the genus Cryptococcus that causes a significant global burden of disease in both immunocompromised and immunocompetent individuals. Over the past several decades, diagnosis and management of cryptococcal disease have moved to focus on rapid, reliable, and cost-effective care delivery, with the advent of new antigen detection assays and novel antifungal treatment strategies.

Evaluation of Inborn Errors of Immunity Among Patients with Opportunistic Pulmonary Infection

This review of immunocompromised host pneumonia as the result of inborn errors of immunity (IEI) is organized by opportunistic pulmonary pathogen. The authors identify patients who warrant an evaluation for an IEI based on their clinical presentation. Their recommendations are guided by the immune defect(s) associated with each opportunistic pulmonary infection. Physicians without expertise in immunology may begin an evaluation for IEI using the guidance provided here. Comprehensive evaluation by an immunologist may also be warranted in many instances.

Non-Neoformans Cryptococcal Infections in the Post-Coronavirus Disease-19 (COVID-19) Era: Are We Ready to Face the Emerging Challenge?

Coronaviruses are a large group of viruses that infect animals as well as humans, while it is also suggested that, rarely, coronaviruses that infect animals can evolve and infect humans. Current evidence suggests that severe acute respiratory syndrome (SARS) coronavirus-2 leads to coronavirus disease-19 (COVID-19), the respiratory illness responsible for COVID-19 pandemic, while it has a zoonotic origin, closely related to the bat-origin SARS-like coronavirus. Also, as per the current knowledge, the disease may induce significant and persistent lymphopenia which in turn may increase the risk for various opportunistic infections. Cryptococcus laurentii is one such rare, but serious fungal infection which has been reported in post-COVID-19 disease and is a rising cause of concern since it can turn out to be fatal. The infection is caused by a non-neoformans rare human pathogen. The present case report describes the case of a 45-years old male patient who reported to the Outpatient Department (OPD) for a routine dental complaint with a grossly destructed tooth in left lower back tooth region due to extensive carious involvement, while, simultaneously, presenting with fever since 5 days in the post-COVID-19 phase, and was later diagnosed as being positive for C. laurentii infection on urine culture sensitivity test.

Therapeutic role of fluconazole in immunocompetent patients with pulmonary cryptococcosis: A case report

The present investigation examines the potential for customized treatment of pulmonary cryptococcosis using fluconazole in an immunocompetent individual. Therapeutic drug monitoring (TDM) was utilized throughout treatment to assess fluconazole levels. Research indicated that the MIC90 for cryptococcus in China is around 8 mg/L. We evaluated the area under the curve (AUC) relative to the minimal inhibitory concentration (MIC), focusing on the AUC from 0 to 24 h (AUC0-24 h/MIC). Fluconazole's dosage was adjusted according to pharmacokinetics/pharmacodynamics (PK/PD) principles to enhance therapeutic efficacy. Post-treatment evaluation showed marked improvement in the patient's condition, with lesions exhibiting partial absorption.

Speckled-egg staining appearance of cryptococcal osteomyelitis in an immunocompetent patient

Introduction

Cryptococcal infections are typically thought of as occurring in immunocompromised patients, such as patients with HIV/AIDS, solid organ transplant recipients, or patients with rheumatologic diseases that require immunomodulatory therapy. Moreover, Cryptococcus spp. classically appear as variably-sized yeasts with narrow-based budding surrounded by a thick polysaccharide capsule. However, cryptococcal infections are being increasingly reported in atypical hosts, at times with non-characteristic histochemical staining appearances. Herein, we report a case of cryptococcal osteomyelitis in an otherwise immunocompetent individual that had a "speckled-egg" staining appearance on direct-smear Gram stain.

Case

The patient is an otherwise healthy 89-year-old male with a past medical history notable only for hypertension who presented with progressive left-sided neck pain that became worse despite lidocaine trigger point injections; imaging was obtained and revealed a C1-C2 prevertebral abscess, C2-C4 osteomyelitis, and a small C2-C4 abscess. An aspiration biopsy from one of the cervical abscesses grew Cryptococcus neoformans. Despite prompt initiation of liposomal amphotericin B as soon as the organism was suspected, the patient's mentation declined with associated progression of weakness in his upper and lower extremities. The patient was ultimately transitioned to comfort care.

Conclusions

Unconventional presentations of cryptococcal disease are becoming increasingly recognized in seemingly immunocompetent patients. Our case was unique given that it occurred in a patient who appeared to be immunocompetent and the Gram stain showed a speckled-egg staining pattern that alone was not distinctive for cryptococcal yeasts. Despite the patient's lack of any classic comorbidities associated with invasive cryptococcal disease, his advanced age was likely a risk factor.

Lateral flow assay as radiological prognosis factor of pulmonary cryptococcosis: a single center retrospective study in China

Background

Lateral flow assay (LFA) has demonstrated high sensitivity and specificity for diagnosing cryptococcosis. However, its role in predicting therapeutic efficacy for pulmonary cryptococcosis (PC) remains underexplored.

Methods

We conducted a retrospective analysis of HIV-negative patients with PC to describe the clinical profile and identify potential predictors of radiological prognosis.

Results

All the 168 participants received antifungal therapy with a triazole agent. Of these, 84.5% experienced partial or complete absorption of pulmonary lesions. The results of the gamma test, chi-square trend test, and ordinal logistic regression all indicated that both baseline LFA and changes in LFA after treatment were significant predictors of imaging prognosis. The degree of radiological improvement was inversely associated with the baseline LFA positive grade(P for linear-by-linear association: 0.011, Spearman correlation coefficient = -0.17; γ= -0.368, P = 0.045). Patients with a decrease in LFA after therapy had significantly better radiological outcomes compared to those with equal or increased LFA(linear-by-linear association, P = 0.014, Spearman correlation coefficient = 0.188; γ = 0.371, P = 0.012). Additionally, favorable outcomes were more likely in patients with lesions confined to the right lung.

Conclusions

LFA shows potential of monitoring radiological outcomes in pulmonary cryptococcosis.

Pulmonary cryptococcosis associated with Cryptococcus neoformans in an immunocompetent child

We report a pediatric case of pulmonary cryptococcosis caused by Cryptococcus neoformans in an immunocompetent child. Although the patient presented with mild clinical symptoms, pulmonary imaging revealed severe abnormalities. The diagnosis was confirmed through fungal culture of bronchoalveolar lavage fluid and detection of serum cryptococcal antigen. An appropriate and adequately administered course of antifungal treatment led to a favorable prognosis.

A case of pneumonia caused by infection with Tropheryma whipplei complicated by cryptococcus during treatment with a Janus kinase inhibitor: a case report

This report describes the case of a 41-year-old male patient complaining of a hacking cough. The patient was treated with a Janus kinase (JAK) inhibitor for psoriasis. Blood tests revealed mild lymphopenia and high levels of serum cryptococcal antigen. Chest computed tomography revealed infection in the lower lobe of the left lung. Metagenomic next-generation sequencing of bronchoalveolar lavage fluid revealed Tropheryma whipplei. Tropheryma whipplei and Cryptococcus antimicrobial therapies were sequentially administered. During follow-up, the patient showed clinical and radiographic improvement. Tropheryma whipplei is an opportunistic Gram-positive rod-shaped bacterium belonging to the family Actinomycetes. Lung involvement is an unusual but classic manifestation of Whipple's disease. This is the first report of pneumonia caused by infection with Tropheryma whipplei complicated by Cryptococcus. To our knowledge, this is the first case report of Tropheryma whipplei infection following the use of JAK inhibitors. Clinicians should be aware of opportunistic infections that can occur during treatment with JAK inhibitors.

Minimal domain peptides derived from enterocins exhibit potent antifungal activity

The antimicrobial peptide (AMP) circularized bacteriocin enterocin AS-48 produced by Enterococcus sp. exhibits broad-spectrum antibacterial activity via dimer insertion into the plasma membrane to form membrane pore structures, compromising membrane integrity and leading to bactericidal activity. A specific alpha-helical region of enterocin AS-48 has been shown to be responsible for the membrane-penetrating activity of the peptide. The canon syn-enterocin peptide library, generated using rational design techniques to have ninety-five synthetic peptide variants from the truncated, linearized, membrane-interacting domain of enterocin AS-48, was screened against three clinically relevant fungal strains: Cryptococcus neoformans, Candida albicans, and Candida auris for potential antifungal activity. Twelve peptides exhibited antifungal activity against C. neoformans, and two peptides exhibited activity against C. albicans. The fourteen active antifungal peptides were minimally cytotoxic to an immortalized human keratinocyte cell line (HaCats). Four select peptides were identified with minimum inhibitory concentrations (MICs) below 8 µM against C. neoformans. In 36-hour cell growth tests with these fungicidal peptides, fungicidal peptide no. 32 displayed inhibitory properties comparable to the leading antifungal medication fluconazole against C. neoformans. Screening of peptide no. 32 against a deletion library of C. neoformans mutants revealed that the mechanism of action of peptide no. 32 may relate to multivesicular bodies (MVBs) or polysaccharide capsule targeting. These findings importantly demonstrate that naturally derived AMPs produced by bacteria can be sourced, engineered, and modified to exhibit potent antifungal activity. Our results will contribute to the development of broad treatment alternatives to fungal infections and lend themselves to direct implications for possible treatment options for C. neoformans infections.

Clinical characteristics of pulmonary cryptococcosis patients with different immune statuses: A 10-year multicenter retrospective study in China

BACKGROUND AND OBJECTIVE

We aimed to evaluate clinical characteristics and therapeutic efficacy of pulmonary cryptococcosis (PC) in patients with different immune status in a large multicenter population to support appropriate clinical management of this public health threat.

METHODS

We retrospectively investigated the medical records of 510 patients with PC from January 2014 to June 2023 in 10 representative regional tertiary teaching hospitals in Hubei province of China, and clinical data of these patients were then stratified by different immune statuses.

RESULTS

Immunocompetent (IC) patients accounted for 68.8 % (351/510), mild-to-moderate immunodeficiency (MID) patients accounted for 16.7 % (85/510), and severe immunodeficiency (SID) patients accounted for 14.5 % (74/510). PC patients in the MID and SID groups had a higher incidence of central nervous system (CNS) involvement than that in the IC group [4.7 % (MID) vs. 8.1 % (SID) vs. 1.1 % (IC), p = 0.002]. Patients with fever in SID group (35.1 %, 26/74) was more common (p < 0.01). Solitary nodule/mass were more common in the IC group than the MID and SID groups (p < 0.05); in contrast, diffuse nodules in MID or SID groups was significantly greater than that in IC groups (p < 0.01). The follow-up showed that the overall treatment improvement rate for PC showed a significant difference between the 3 groups [90.3 % (IC) vs. 75.3 % (MID) vs. 54.1 % (SID), p = 0.00].

CONCLUSION

The incidence of PC is increasing in Central China, especially for the immunocompetent PC population. In addition, there are significant differences in age, systemic symptoms, certain radiographic characteristics and some laboratory results between immunosuppressed and immunocompetent PC hosts. And finally, limited nodules/masses and mild symptoms in patients with PC often lead to misdiagnosis and unnecessary pulmonary resection, but CrAg assay contributes to early noninvasive diagnosis.

Clinical imaging diagnosis of pulmonary cryptococcosis with different therapeutic responses

We aimed to differentiate and evaluate the clinical imaging features of pulmonary cryptococcosis with different therapeutic responses. The clinical imaging data of 70 patients with PC (complete response PC 37 cases and incomplete response PC 33 cases) were collected and compared to determine the independent risk factors for different therapeutic responses, and their diagnostic performances were verified by receiver operating characteristic curve analysis. Compared with complete response PC, incomplete response PC was more common with immunosuppression (10.8% vs. 45.5%, P = 0.001), intermediate progress (8.1% vs. 39.4%, P = 0.002), bilateral distribution (21.6% vs. 78.8%, P < 0.001), consolidation-interstitial pattern (10.8% vs. 42.4%, P = 0.003), pleural effusion (0 vs. 27.3%, P = 0.002) and mediastinal lymphadenopathy (0 vs. 24.2%, P = 0.005). Multivariate logistic regression showed that immunosuppression, intermediate progress, and bilateral distribution were independent risk factors, with low to moderate areas under curves (AUC, 0.656-0.786). Their combined performance was good with an AUC of 0.888. The diverse clinical imaging features can reflect the therapeutic response of PC. Immunosuppression, intermediate progress, and bilateral distribution were independent risk factors. Their combination can significantly improve diagnostic effects.

A rare case of cryptococcal meningitis with infarction of the splenium of the corpus callosum in an immunocompetent patient: A case report

Meningitis is a severe infection of the central nervous system. Cryptococcus neoformans is an uncommon fungal agent that can cause meningitis and often manifests unusual symptoms. While this infection is more prevalent in immunocompromised patients, it can also affect immunocompetent patients. A 33-year-old housewife living in the village visited our hospital emergency department complaining of a severe headache and mild fever for 7 days. We diagnosed an unusual occurrence of cryptococcal meningitis with infarction of the splenium of the corpus callosum in a patient who appeared to have a healthy immune system. This disease should be considered in immunocompetent individuals with persistent headache or other neurological findings, even in the absence of overt risk factors.

Dose Optimization of Fluconazole After Initial Treatment Failure in Pulmonary Cryptococcosis in an Obese Patient with Type 2 Diabetes and Cirrhosis: A Case Report

Background

Pulmonary cryptococcosis is a fungal infection of the lungs, particularly challenging to treat in patients with multiple comorbidities such as obesity, type 2 diabetes, and cirrhosis. Fluconazole is a first-line medication for the treatment of pulmonary cryptococcosis, but currently there is a lack of clinical medication experience in obese patients with multiple comorbidities, especially in dose adjustment after treatment failure.

Case Introduction

This case report describes the experience of fluconazole in the treatment of pulmonary cryptococcal infection in a 45-year-old Chinese male with obesity, type 2 diabetes, and cirrhosis. The patient had a history of antifungal therapy for two weeks before admission, but the cough and hemoptysis were not improved. The treatment failed. After admission, it was recommended to use a conventional dose of fluconazole as an antifungal regimen according to the guidelines. However, the treatment effect was still unsatisfactory, due to the patients' cough, hemoptysis, and fever symptoms were not relieved. During this period, it was newly found that the patient had cirrhosis and type 2 diabetes and had not previously controlled blood glucose. Considering the above situation, combined with the pharmacokinetic characteristics of fluconazole and the patient's weight reaching 113 kg, the team readjusted the fluconazole medication regimen, and ultimately, the pulmonary infection improved without significant adverse reactions.

Results

We found that it was more suitable for patients with obesity to calculate the dose of fluconazole by the lean weight. By estimation, the patient was finally given a loading dose of 800 mg fluconazole, and his condition improved significantly. After two weeks of medication, it was adjusted to a maintenance dose of 600 mg until the pulmonary infection in the patient disappeared.

Conclusion

This case suggests that fluconazole antifungal therapy for pulmonary cryptococcal infection should fully consider the risk of comorbidities in patients. If necessary, medication dosage can be adjusted according to weight, and it is recommended to use lean bodyweight for evaluation and optimization. In addition, close attention should be paid to liver and kidney function.

Bronchoalveolar lavage fluid and lung biopsy tissue metagenomic next-generation sequencing in the diagnosis of pulmonary cryptococcosis

Objective

To evaluate the diagnostic value of metagenomic next-generation sequencing (mNGS) in pulmonary cryptococcosis (PC) using bronchoalveolar lavage fluid (BALF) and lung biopsy tissue specimens.

Methods

In this retrospective study, 321 patients diagnosed with lower respiratory tract diseases who underwent mNGS using BALF and LBT samples, between January 2021 and December 2023 were included. Individuals were classified into PC and non-PC groups according to the diagnostic criteria for PC, and conventional fungal cultures were performed. A serum/BALF cryptococcal antigen (CrAg) test was performed in some patients with PC. The diagnostic efficiencies of three methods for PC (mNGS, conventional culture, and CrAg) were compared. Additionally, two mNGS methods were used in this study: original mNGS (OmNGS, testing time from January 2021 to December 2022) and modified mNGS (MmNGS, testing time from January to December 2023). The diagnostic efficiency of the two mNGS methods on PC was simultaneously compared.

Results

Among the 321 patients, 23 (7.2%) had PC and 298 (92.8%) did not. Compared with the composite reference standard for PC diagnosis, the sensitivity, specificity, and accuracy of mNGS for PC were 78.3% (95% confidence interval [CI], 55.8%-91.7%), 98.7% (95% CI, 96.4%-99.6%), and 97.2% (95% CI, 94.7%-98.7%), respectively. The sensitivity of mNGS was similar to that of CrAg (80.0%, 12/15) (P > 0.05). The diagnostic sensitivity of both mNGS and CrAg was higher than that of conventional culture (35.0%, 7/20) (P = 0.006, P = 0.016), and the combined detection of mNGS and CrAg further improved the diagnostic sensitivity of PC (93.3%, 14/15). The area under the receiver operating characteristic curve of mNGS was superior to that of conventional culture (0.885 vs. 0.675). In addition, the diagnostic sensitivity of PC was higher than that of OmNGS (P = 0.046).

Conclusion

The sensitivity of mNGS is better than that of conventional culture. The combination of mNGS and CrAg improves the testing sensitivity of Cryptococcus. MmNGS could further improve the detection of Cryptococcus. Conventional PC detection methods are indispensable and mNGS can be used as a rapid and accurate auxiliary diagnostic method for PC.

LincR-PPP2R5C deficiency enhancing the fungicidal activity of neutrophils in pulmonary cryptococcosis is linked to the upregulation of IL-4

Pulmonary cryptococcosis is a common complication in immunocompromised patients. In a mouse model of pulmonary cryptococcosis, Cryptococcus neoformans induces a type 2 immune response that is detrimental to host protection. Long non-coding RNAs (lncRNAs) have emerged as key players in the pathogenesis of infectious diseases. However, the roles and mechanisms of lncRNAs in fungal infection are largely elusive. In the present study, we aimed to explore the roles of LincR-PPP2R5C in pulmonary cryptococcosis. We observed an increase in the level of LincR-PPP2R5C in the lung tissues of C57BL/6J mice after tracheal infection with C. neoformans. Subsequently, we intratracheally infected LincR-PPP2R5C knockout (KO) mice and wild-type mice with C. neoformans. LincR-PPP2R5C deficiency mitigates C. neoformans infection, which can be demonstrated by extending survival time and decreasing fungal burden in the lung. In the lung tissues of infected LincR-PPP2R5C KO mice, there was a notable increase in the levels of type 2 cytokines [interleukin (IL)-4 and IL-5] and an increase in the number of neutrophils in both the lung tissue and bronchoalveolar lavage fluid. Mechanistically, the lack of LincR-PPP2R5C results in increased protein phosphatase 2A phosphorylation, thereby enhancing the fungicidal activity of neutrophils against Cryptococcus neoformans, with IL-4 playing a synergistic role in this process. Overall, LincR-PPP2R5C deficiency mitigated pulmonary cryptococcosis by increasing the fungicidal activity of neutrophils, which was associated with increased IL-4 levels. Our study presented specific evidence of the role of host-derived lncRNAs in the regulation of C. neoformans infection.

IMPORTANCE

Pulmonary cryptococcosis is a human fungal disease caused by Cryptococcus neoformans, which is common not only in immunocompromised individuals but also in patients with normal immune function. Therefore, studying the control mechanisms of pulmonary cryptococcosis is highly important. Here, we demonstrated that the deletion of LincR-PPP2R5C leads to increased killing of C. neoformans by neutrophils, thereby reducing pulmonary cryptococcal infection. These findings will greatly enhance our understanding of the mechanisms by which lncRNAs regulate the pathogenesis of C. neoformans, facilitating the use of lncRNAs in pulmonary cryptococcosis therapy.

A rare case of disseminated pulmonary cryptococcosis in an immunocompetent patient

Pulmonary cryptococcosis is an uncommon invasive fungal infection of the lungs seen in immunocompromised individuals but increasingly reported among the immunocompetent. We report a rare case of pulmonary cryptococcosis in an immunocompetent host highlighting its unique clinical and radiological presentation.Clinical trial number: Not applicable.

Clinical characteristics and prognostic factors of pulmonary and extrapulmonary cryptococcosis

BACKGROUND

Cryptococcosis is progressively acknowledged among people, irrespective of the human with or without immunodeficiency virus (HIV). This change in epidemiology has been recorded in recent years, prompting closer examination and a broader understanding of the disease manifestations and risk factors.

METHODS

The data of cryptococcal infections in China during 11 years were retrospectively analyzed. According to the position of infection, the patients were categorized into the pulmonary infection group and extrapulmonary infection group. The composition of the two groups was compared, and the potential risk factors of disseminated infection were analyzed. Logistic regression was used to analyze the prognostic risk factors of the disease.

RESULTS

A total of 165 patients were enrolled. 113 (68.5%) were male, and the age was 47.49 (18-82) years. 101 cases (61.2%) had a normal immune function and 64 cases (38.8%) had impaired immune function. 45 patients had extrapulmonary infection, involving the central nervous system, bone and joint, skin and bloodstream, and 120 patients had simple pulmonary infection. The mortality of the extrapulmonary infection group (48.9%) was significantly higher than that of the pulmonary infection group (0.8%). According to univariate logistic regression analysis, immune status (hazard ratio [HR], 4.476; 95% confidence interval [CI], 1.725-11.618; P = 0.002), infection position ([HR], 113.826; [CI], 14.607-886.967; P < 0.001), white blood cell count, ([HR],1.209;[CI], 1.054-1.386; P = 0.007), hemoglobin ([HR], 0.970; [CI], 0.955-0.986; P < 0.001), platelet count ([HR], 0.993; [CI], 0.987-0.999; P = 0.026), neutrophil percentage ([HR], 1.115; [CI], 1.065-1.168; P < 0.001), lymphocyte percentage ([HR], 0.875; [CI], 0.827-0.927; P < 0.001), neutrophil-to-lymphocyte Ratio (NLR) ([HR], 1.144; [CI], 1.072-1.221; P < 0.001), monocyte percentage ([HR], 0.752; [CI], 0.618-0.915; P = 0.004) were related to the prognosis. Multivariate logistic regression analysis showed that the infection position was remained related to the prognosis with statistical significance ([HR], 0.018; [CI], 0.001-0.384; P = 0.001).

CONCLUSION

Extrapulmonary infection of Cryptococcosis is an important risk factor for prognosis. High levels of neutrophils and NLR, and low levels of lymphocytes and monocytes may lead to disseminated infection of Cryptococcosis. Further studies are needed to reduce the occurrence rate of extrapulmonary infection and mortality.

Pulmonary cryptococcosis in chronic kidney disease

Pulmonary cryptococcosis is a fungal infection caused by Cryptococcus species, with Cryptococcus neoformans being the most common agent, affecting the lungs. While it commonly occurs in immunocompromised individuals, such as those with HIV/AIDS or undergoing immunosuppressive therapy, its presentation in patients with chronic kidney disease (CKD) is relatively rare. However, it should be considered in the differential diagnosis of respiratory infections in patients with CKD, particularly in the context of immunosuppression.

Lung adenocarcinoma concurrent with pulmonary cryptococcosis: a case report and literature review

Pulmonary cryptococcosis (PC) is a common opportunistic fungal infection caused by Cryptococcus neoformans or Cryptococcus gattii. PC primarily invades the respiratory system, followed by the central nervous system. Few clinical reports have examined the coexistence of PC and lung cancer. This study reports the case of a 54-year-old immunocompetent PC patient with lung adenocarcinoma. Chest CT revealed multiple nodules in the right lung, with the largest nodule located in the dorsal segment of the right lower lobe. 18 F‑FDG positron emission tomography-computed tomography (PET-CT) revealed elevated glucose metabolism in the dorsal segment of the right lower lobe, which suggested lung cancer. The metabolism level of the nodule in the basal segment of the right lower lobe and the anterior segment of the right upper lobe was not abnormally increased, but the possibility of a malignant tumour could not be excluded. The pulmonary nodules in the dorsal segment and the basal segment of the right lower lobe were simultaneously resected via video-assisted thoracic surgery (VATS), and the final histopathology revealed primary lung adenocarcinoma and pulmonary cryptococcal infection, respectively. After surgery, antifungal treatment was administered for 3 months. Over the 3-year follow-up, contrast-enhanced computed tomography (CT) revealed no recurrence of either disease. This case study highlights the possibility of dualism in the diagnosis of multiple pulmonary nodules on chest CT, such as the coexistence of lung cancer and PC. Surgical resection is recommended for micronodules that are not easy to diagnose via needle biopsy; in addition, early diagnosis and treatment are helpful for ensuring a good prognosis. This paper reports the clinical diagnosis and treatment of one patient with pulmonary cryptococcal infection of the right lung complicated with lung adenocarcinoma, including 3 years of follow-up, providing a reference for clinical practice.

Fungal Extracellular Vesicle Proteins with Potential in Biological Interaction

Extracellular vesicles (EVs) are vesicle-like structures composed of lipid bilayers, which can be divided into apoptotic bodies, microbubbles and exosomes. They are nanoparticles used for the exchange of information between cells. EVs contains many substances, including protein. With the development of proteomics, we know more about the types and functions of protein in vesicles. The potential functions of proteins in the envelope are mainly discussed, including cell wall construction, fungal virulence transmission, signal transmission and redox reactions, which provides a new perspective for studying the interaction mechanism between fungi and other organisms. The fungal protein markers of EVs are also summarized, which provided an exploration tool for studying the mechanism of vesicles. In addition, the possible role of immune protein in the EVs in the treatment of human diseases is also discussed, which provides new ideas for vaccine development.

Elucidation of furanone as ergosterol pathway inhibitor in Cryptococcus neoformans

In the era of antiretroviral therapy, the prevalence of Cryptococcal infection among HIV patients in developed countries has decreased considerably. However, C. neoformans ranks top among the critical priority pathogen that affects a wide range of immunocompromised individuals. The threat of C. neoformans is because of its incredibly multifaceted intracellular survival capabilities. Cell membrane sterols especially ergosterol and enzymes of its biosynthetic pathway are considered fascinating drug targets because of their structural stability. In this study, the ergosterol biosynthetic enzymes were modeled and docked with furanone derivatives. Among the tested ligands Compound 6 has shown a potential interaction with Lanosterol 14 α-demethylase. This best-docked protein-ligand complex was taken further to molecular dynamics simulation. In addition, Compound 6 was synthesized and an in vitro study was conducted to quantify the ergosterol in Compound 6 treated cells. Altogether the computational and in vitro study demonstrates that Compound 6 has anticryptococcal activity by targeting the biosynthetic pathway of ergosterol.Communicated by Ramaswamy H. Sarma.

Cryptococcal meningoencephalitis and pneumonia in a HIV positive patient: A case report

Key Clinical Messages

Early diagnosis of cryptococcal infection is the key to improving outcomes, any newly diagnosed HIV patient presenting with subacute or chronic headache, particularly those who are CD4-deplete, should be investigated for cryptococcal meningitis. We had some delay in our patient management, including delay in HIV diagnosis, delay in doing LP and delay in initiation of anti-cryptococcal treatment and also early start of ART before specific cryptococcal treatment exacerbated IRIS in the patient. So, paying attention to these points can improve the prognosis of such patients.

Abstract

Cryptocccus is a fungal pathogen and the causative agent of Cryptococcosis among human immunodeficiency virus (HIV) positive people. Meningoencephalitis is the most common manifestation of cryptococcal infection, while pulmonary cryptococcosis is often neglected due to nonspecific clinical and radiological presentation leading to a delay in diagnosis and disseminated disease. Here, we reported a 67-year-old man with newly diagnosed HIV who presented with concurrent cryptococcal meningoencephalitis and pulmonary cryptococcosis that admitted with the complaint of dyspnea and productive cough for 1.5 months, worsening shortness of breath, fever and weight loss since 15 days prior to admission. He also had severe oral candidiasis. Lung computed tomography (CT) revealed ill-defined subpleural cavitary lesion in left lower zone with bilateral diffuse ground glass opacity and air bronchogram. His HIV PCR test was positive with absolute CD4 count less than 50 cells/mm3. After starting antiretroviral therapy (ART), he gradually developed a headache and decreased level of consciousness. Cerebrospinal fluid (CSF) analysis revealed 450 cells, predominantly lymphocytes, with protein of 343 mg/dL and glucose of 98 mg/dL (corresponding blood glucose 284 mg/dL). CSF India ink staining was positive for crypococcus spp. Liposomal amphotericin B in combination with fluconazole (due to the unavailability of flucytosin) was stated. He was intubated because of hypoxia and his bronchoalveolar lavage was positive for Cryptococcus spp. too. He died 2 weeks after starting antifungal therapy based on this study it should be mentioned that neurologic and respiratory symptoms may be the first presentation of acquired immunodeficiency syndrome.

All hands on Dec: Treating cryptococcosis with dectin decorated liposomes loaded with antifungals

Systemic cryptococcosis is often fatal even with the current antifungal therapy and there is no vaccine available. Induction therapy with amphotericin B (AmB) is essential for its treatment, which can be either in the form of AmB deoxycholate at 1 mg/kg/day for 7 days or a single dose of liposomal AmB (AmB-LLs) at 10 mg/kg, both in combination with flucytosine. AmB is highly toxic and it is imperative to further increase its efficacy without increasing its toxicity. Previously, we developed a targeted antifungal drug delivery system (DectiSome) that uses liposomes decorated with host-pathogen receptor dectins to target AmB to fungal cells. Here, we showed that a single dose of Dectin-2 coated liposomal AmB, relative to AmB-LLs, reduced fungal burden and prolonged animal survival in the murine model of systemic cryptococcosis. Our results demonstrate that DectiSomes are a promising antifungal delivery system that could improve cryptococcosis therapy in the future.

Establishment of a predictive model of CT value in the diagnosis and differential diagnosis of pulmonary cryptococcosis

Objective

To investigate the application value of computed tomography (CT) value (HU) in the diagnosis and differential diagnosis of pulmonary cryptococcosis (PC) and to construct a prediction model.

Methods

Retrospective analysis of the clinical data of 73 patients who presented with nodular/mass-type occupations on lung CT and confirmed by histopathology in our hospital from January 2019 to May 2022 were divided into PC group (23 patients) and non-PC group (50 patients) according to the pathological findings, and the CT values of each patient's lung lesions were measured. The differences in age, gender, symptoms, lesion involvement in one/both lungs, lung lobe distribution, number of lesions, maximum lesion diameter (cm), lesion margin condition, and CT value results were compared between the two groups. Independent risk factors for PC were analyzed for indicators with statistically significant differences, clinical prediction models were constructed and column line plots were drawn, C (correction) indices were calculated, subject characteristics (ROC) curves were drawn, calibration curves and clinical decision curve analysis (DCA) were performed to further evaluate the predictive efficacy of the models.

Results

Comparative analysis of patient data between the two groups showed statistically significant differences in central, peripheral and global CT values (P < 0.05), and multiple regression analysis indicated that central CT value, peripheral CT value and global CT value could be used as independent risk factors for the diagnosis and differential diagnosis of PC. The area under the ROC curve of the model predicting PC was 0.814 (95 % CI: 0.7011-0.9267), and the corrected C-index (Bootstrap = 1000) was 0.781; the actual curve overlapped well with the calibration curve; the DCA results indicated that the column line graph model has high clinical application value.

Conclusions

CT value measurements of lesions can be used as an independent risk factor for PC, and clinical prediction models based on the above factors are predictive for the diagnosis and differential diagnosis of PC.

Granulomatous Lung Diseases: A Practical Approach and Review of Common Entities

Granulomas are frequently encountered by pathologists in all types of lung specimens and arise from diverse etiologies. They should always be reported as necrotizing or non-necrotizing, with microorganism stains performed to evaluate for infection. With attention to distribution, quality (poorly vs well-formed), associated features, and correlation with clinical, radiologic, and laboratory data, the differential diagnosis for granulomatous lung disease can usually be narrowed to a clinically helpful "short list." This review describes a practical approach to pulmonary granulomas and reviews the clinicopathological aspects of common entities, including infectious (mycobacteria, fungi) and noninfectious (hypersensitivity pneumonitis, sarcoid, and vasculitis) causes.

Clinical, radiological, and laboratory features of HIV-negative pulmonary cryptococcosis with regard to serum lateral flow assay

Introduction

Cryptococcosis is the second most common invasive yeast infection in China. Pulmonary cryptococcosis (PC) is difficult to diagnose due to the lack of specific clinical features and the limitation of diagnostic techniques. Although lateral flow assay was very useful in diagnosing cryptococcal infection, quite a few patients with PC presented negative serum lateral flow assay (sLFA).

Methods

We conducted a retrospective study of HIV-negative patients who were diagnosed with PC in our hospital over the past decade to explore the potential relationship between the clinical profiles and sLFA in PC.

Results

In total, 112 patients with sLFA tested were enrolled in this study, of which 58.93% were male. The positivity rate of sLFA for PC was 91.07%. The extent of pulmonary lesions was positively correlated with sLFA grade (Spearman r = 0.268, p < 0.01). Solitary nodule (SN) and pneumonia were the most common imaging findings in PC with negative and positive sLFA respectively. Among 65 symptomatic PC patients, 14 presented with fever and had higher hypersensitive C-reactive protein (hsCRP) level and more extensive pulmonary involvement (Mann-Whitney U test, p < 0.05) than those without fever. Symptomatic PC patients were more likely to have positive results of sLFA (Mann-Whitney U test, p = 0.05) compared against asymptomatic ones.

Discussion

In conclusion, negative sLFA cannot exclude PC in patients with a solitary nodule in lung. Positive sLFA is more reliable in diagnosing PC in symptomatic patients with diffused lesions in lung who generally experience a more severe systemic inflammatory reaction.

A nomogram to predict cryptococcal meningitis in patients with pulmonary cryptococcosis

Background

The most serious manifestation of pulmonary cryptococcosis is complicated with cryptococcal meningitis, while its clinical manifestations lack specificity with delayed diagnosis and high mortality. The early prediction of this complication can assist doctors to carry out clinical interventions in time, thus improving the cure rate. This study aimed to construct a nomogram to predict the risk of cryptococcal meningitis in patients with pulmonary cryptococcosis through a scoring system.

Methods

The clinical data of 525 patients with pulmonary cryptococcosis were retrospectively analyzed, including 317 cases (60.38 %) with cryptococcal meningitis and 208 cases (39.62 %) without cryptococcal meningitis. The risk factors of cryptococcal meningitis were screened by univariate analysis, LASSO regression analysis and multivariate logistic regression analysis. Then the risk factors were incorporated into the nomogram scoring system to establish a prediction model. The model was validated by receiver operating characteristic (ROC) curve, decision curve analysis (DCA) and clinical impact curve.

Results

Fourteen risk factors for cryptococcal meningitis in patients with pulmonary cryptococcosis were screened out by statistical method, including 6 clinical manifestations (fever, headache, nausea, psychiatric symptoms, tuberculosis, hematologic malignancy) and 8 clinical indicators (neutrophils, lymphocytes, glutamic oxaloacetic transaminase, T cells, helper T cells, killer T cells, NK cells and B cells). The AUC value was 0.978 (CI 96.2 %∼98.9 %), indicating the nomogram was well verified.

Conclusion

The nomogram scoring system constructed in this study can accurately predict the risk of cryptococcal meningitis in patients with pulmonary cryptococcosis, which may provide a reference for clinical diagnosis and treatment of patients with cryptococcal meningitis.

Postpartum cryptococcosis in an HIV-negative patient

PURPOSE AND METHODS

We present an unusual case of an HIV-negative patient with postpartum pulmonary cryptococcosis and cryptococcemia.

RESULTS

The diagnostic methods and treatment of cryptococcosis in a postpartum patient are presented in this case report. Due to anaphylaxis to liposomal amphotericin B, desensitisation to the drug was performed.

CONCLUSION

We would like to raise awareness about rare infections such as cryptococcosis in pregnancy and the postpartum period. In addition, we were able to document a successful desensitisation to liposomal amphotericin B.

Construction and validation of a nomogram model to predict the poor prognosis in patients with pulmonary cryptococcosis

Background

Patients with poor prognosis of pulmonary cryptococcosis (PC) are prone to other complications such as meningeal infection, recurrence or even death. Therefore, this study aims to analyze the influencing factors in the poor prognosis of patients with PC, so as to build a predictive nomograph model of poor prognosis of PC, and verify the predictive performance of the model.

Methods

This retrospective study included 410 patients (78.1%) with improved prognosis of PC and 115 patients (21.9%) with poor prognosis of PC. The 525 patients with PC were randomly divided into the training set and validation set according to the ratio of 7:3. The Least Absolute Shrinkage and Selection Operator (LASSO) algorithm was used to screen the demographic information, including clinical characteristics, laboratory test indicators, comorbidity and treatment methods of patients, and other independent factors that affect the prognosis of PC. These factors were included in the multivariable logistic regression model to build a predictive nomograph. The receiver operating characteristic curve (ROC), calibration curve and decision curve analysis (DCA) were used to verify the accuracy and application value of the model.

Results

It was finally confirmed that psychological symptoms, cytotoxic drugs, white blood cell count, hematocrit, platelet count, CRP, PCT, albumin, and CD4/CD8 were independent predictors of poor prognosis of PC patients. The area under the curve (AUC) of the predictive model for poor prognosis in the training set and validation set were 0.851 (95% CI: 0.818-0.881) and 0.949, respectively. At the same time, calibration curve and DCA results confirmed the excellent performance of the nomogram in predicting poor prognosis of PC.

Conclusion

The nomograph model for predicting the poor prognosis of PC constructed in this study has good prediction ability, which is helpful for improving the prognosis of PC and further optimizing the clinical management strategy.

Use of 2D minilungs from human embryonic stem cells to study the interaction of Cryptococcus neoformans with the respiratory tract

Organoids can meet the needs between the use of cell culture and in vivo work, bringing together aspects of multicellular tissues, providing a more similar in vitro system for the study of various components, including host-interactions with pathogens and drug response. Organoids are structures that resemble organs in vivo, originating from pluripotent stem cells (PSCs) or adult stem cells (ASCs). There is great interest in deepening the understanding of the use of this technology to produce information about fungal infections and their treatments. This work aims the use 2D human lung organoid derived from human embryonic stem cells (hESCs), to investigate Cryptococcus neoformans-host interactions. C. neoformans is an opportunistic fungus acquired by inhalation that causes systemic mycosis mainly in immunocompromised individuals. Our work highlights the suitability of human minilungs for the study of C. neoformans infection (adhesion, invasion and replication), the interaction with the surfactant and induction of the host's alveolar pro-inflammatory response.

Value of rapid on-site evaluation combined with interventional pulmonology techniques in the diagnosis of pulmonary cryptococcosis

OBJECTIVES

The aim of this study is to evaluate the diagnostic value of rapid on-site evaluation (ROSE) combined with computed tomography-guided percutaneous needle biopsy (CT-PNB) or radial endobronchial ultrasound-guided transbronchial lung biopsy (EBUS-TBLB) for pulmonary cryptococcosis (PC).

METHODS

Clinical data of 33 patients diagnosed with PC at the Third Affiliated Hospital of Soochow University between February 2018 and June 2023 were retrospectively analysed. Patients were divided into the CT-PNB and EBUS-TBLB groups based on the intervention method, and the diagnostic positivity rate and incidence of complications were compared between the two groups.

RESULTS

Compared with the final diagnosis, the positive diagnostic rates of ROSE, histopathology and serum CrAg of all patients were 81.8% (27/33), 72.7% (24/33) and 63.6% (21/33), respectively. The average turnaround times of the three methods were 0.1 (0.1-0.2) h, 96.0 (48.0-120.0) h and 7.8 (4.5-13.6) h, respectively (P < 0.001). The coincidence rate between histopathology and ROSE was 84.8% with a kappa value of 0.574. The positive diagnostic rate for PC was significantly higher in the CT-PNB group than in the EBUS-TBLB group (92.9% vs. 57.9%), and the difference was statistically significant (P < 0.05). Combined with the ROSE results, the positive diagnostic rate in the EBUS-TBLB group increased to 84.2% (16/19).

CONCLUSION

ROSE has commendable accuracy and timeliness, and CT-PNB offers further advantages in this regard. ROSE enhances the diagnostic efficiency of EBUS-TBLB for PC and is safe and effective.

Preclinical Models for Cryptococcosis of the CNS and Their Characterization Using In Vivo Imaging Techniques

Infections caused by Cryptococcus neoformans and Cryptococcus gattii remain a challenge to our healthcare systems as they are still difficult to treat. In order to improve treatment success, in particular for infections that have disseminated to the central nervous system, a better understanding of the disease is needed, addressing questions like how it evolves from a pulmonary to a brain disease and how novel treatment approaches can be developed and validated. This requires not only clinical research and research on the microorganisms in a laboratory environment but also preclinical models in order to study cryptococci in the host. We provide an overview of available preclinical models, with particular emphasis on models of cryptococcosis in rodents. In order to further improve the characterization of rodent models, in particular the dynamic aspects of disease manifestation, development, and ultimate treatment, preclinical in vivo imaging methods are increasingly used, mainly in research for oncological, neurological, and cardiac diseases. In vivo imaging applications for fungal infections are rather sparse. A second aspect of this review is how research on models of cryptococcosis can benefit from in vivo imaging methods that not only provide information on morphology and tissue structure but also on function, metabolism, and cellular properties in a non-invasive way.

Cryptococcosis with pulmonary cavitation in an immunocompetent child: a case report and literature review

BACKGROUND

Pulmonary cryptococcosis (PC) rarely occurs in immunocompetent children.

CASE PRESENTATION

A 13-year-old boy was admitted to the First Affiliated Hospital of Ningbo University in February 2023 with complaints of cough and chest pain. Physical examination showed slightly moist rales in the right lung. Chest computed tomography (CT) suggested a lung lesion and cavitation. Blood routine test, lymphocyte subsets, immunoglobulin, and complement tests indicated that the immune system was normal. However, the serum cryptococcal antigen test was positive. Next-generation sequencing revealed Cryptococcus infection. The child was diagnosed with PC and was discharged after treating with fluconazole 400 mg. Four months later, chest CT showed that the lung lesion diminished, and reexamination of serum cryptococcal antigen test turned positive.

CONCLUSION

PC should be considered in an immunocompetent child with pulmonary cavities with nonspecific symptoms.

Enhancing earthworm (Lumbricus terrestris) tolerance to plastic contamination through gut microbiome fortification with plastic-degrading microorganisms

Microorganisms from L. terrestris gut previously exposed to different types of plastic (PET, LDPE, LLDPE, and PS) were studied to be used as probiotics of earthworms in plastic-contaminated soils (LDPE, LLDPE and recycled mulching film) at mesocosm-scale trials. The most abundant morphotypes with enzymatic capacities of interest were identified. Pseudomonas alkylphenolica (PL4) and Pseudomonas putida (PL5) strains were selected to be used as inoculants using Morus alba leaves as carriers to strengthen the intestinal microbiota of earthworms. Culture (selective cetrimide agar medium) and molecular (qPCR) techniques were used to trace the presence of the inoculum in the intestine of the earthworms. Additionally, a metataxonomic analysis was carried out to study the biodiversity and functionality of the earthworm microbiome, and their measure of survival and weight. Probiotics improved the survival rates of earthworms exposed to plastics, which also increased the abundance of microbial groups of interest in plastic bioremediation tasks.

Pulmonary cryptococcosis coexisting with lung adenocarcinoma: A case report and review of the literature

Pulmonary cryptococcosis (PC) is an invasive pulmonary fungal disease caused by Cryptococcus neoformans or Cryptococcus gattii. It often presents as a single nodule or mass on radiology, which is easily misdiagnosed as lung cancer or metastases. However, cases of PC coexisting with lung cancer are rare and when this scenario is encountered in clinical practice, it is easy to be misdiagnosed as metastatic lung cancer. The present study reported the case of a 65-year-old immunocompetent patient with PC coexisting with lung adenocarcinoma. Percutaneous lung biopsy was performed on the nodule in the anterior segment of the left upper lobe and the nodule in the posterior basal segment of the left lower lobe, which were diagnosed as primary adenocarcinoma and cryptococcus, respectively. Lung cancer was treated by surgery and PC was treated successfully by antifungal treatment. During the 5-year follow-up, contrast-enhanced CT showed no recurrence of either disease. This case reminds us of the possibility of dualism in the diagnosis of multiple pulmonary nodules based on CT examination, such as the coexistence of lung carcinoma and PC. In addition, early diagnosis and treatment contribute to good prognosis.

Whole-genome shotgun sequencing unravels the influence of environmental microbial co-infections on the treatment efficacy for severe pediatric infectious diseases

Background

The microbiome plays a pivotal role in mediating immune deviation during the development of early-life viral infections. Recurrent infections in children are considered a risk factor for disease development. This study delves into the metagenomics of the microbiome in children suffering from severe infections, seeking to identify potential sources of these infections.

Aims

The aim of this study was to identify the specific microorganisms and factors that significantly influence the treatment duration in patients suffering from severe infections. We sought to understand how these microbial communities and other variables may affect the treatment duration and the use of antibiotics of these patients with severe infections.

Method

Whole-genome shotgun sequencing was conducted on samples collected from children aged 0-14 years with severe infections, admitted to the Pediatrics Department of Xiamen First Hospital. The Kraken2 algorithm was used for taxonomic identification from sequence reads, and linear mixed models were employed to identify significant microorganisms influencing treatment duration. Colwellia, Cryptococcus, and Citrobacter were found to significantly correlate with the duration of clinical treatment. Further analysis using propensity score matching (PSM) and rank-sum test identified clinical indicators significantly associated with the presence of these microorganisms.

Results

Using a linear mixed model after removed the outliers, we identified that the abundance of Colwellia, Cryptococcus, and Citrobacter significantly influences the treatment duration. The presence of these microorganisms is associated with a longer treatment duration for patients. Furthermore, these microorganisms were found to impact various clinical measures. Notably, an increase in hospitalization durations and medication costs was observed in patients with these microorganisms. In patients with Colwellia, Cryptococcus, and Citrobacter, we discover significant differences in platelets levels. We also find that in patients with Cryptococcus, white blood cells, hemoglobin, and neutrophils levels are lower.

Conclusion

These findings suggest that Colwellia, Cryptococcus, and Citrobacter, particularly Cryptococcus, could potentially contribute to the severity of infections observed in this cohort, possibly as co-infections. These microorganisms warrant further investigation into their pathogenic roles and mechanisms of action, as their presence in combination with disease-causing organisms may have a synergistic effect on disease severity. Understanding the interplay between these microorganisms and pathogenic agents could provide valuable insights into the complex nature of severe pediatric infections and guide the development of targeted therapeutic strategies.

Pulmonary cryptococcosis complicated with pulmonary aspergillosis: a series of studies and a literature review

BACKGROUND/OBJECTIVE

With the development of society, pulmonary fungal diseases, represented by pulmonary aspergillosis and pulmonary cryptococcosis, have become increasingly common. However, there is a lack of clear understanding regarding coinfection by these two types of fungi in immunocompetent individuals.

METHODS

A retrospective study from 2014 to 2022 and a systematic literature review of original articles published in English were performed. Patients with pulmonary cryptococcosis complicated with pulmonary aspergillosis including 5 in the retrospective study and 6 in the systematic literature review.

RESULT

The diagnosis of concurrent pulmonary cryptococcosis and pulmonary aspergillosis in patients was confirmed through repeated biopsies or surgical resection. Pulmonary cryptococcosis is often diagnosed initially (6/11, 55%), while the diagnosis of pulmonary aspergillosis is established when the lesions become fixed or enlarged during treatment. Transbronchial lung biopsy (3/11, 27%), thoracoscopic lung biopsy (2/11, 18%), and percutaneous aspiration biopsy of the lung (1/11, 9%) were the main methods to confirm concurrent infection. Most patients were treated with voriconazole, resulting in a cure for the coinfection (6/11, 55%).

CONCLUSION

Pulmonary cryptococcosis complicated with pulmonary Aspergillus is an easily neglected mixed fungal infection. During the treatment of lesion enlargement in clinical cryptococcus, we need to watch out for Aspergillus infection.

In Vivo Modeling of Cryptococcus neoformans Infection and Collection of Murine Samples

In vivo models provide advantages to study the progression of disease and to identify potential biomarkers to detect and monitor infections. For the human fungal pathogen Cryptococcus neoformans, murine intranasal models aim to recapitulate natural infection from inhalation of desiccated fungal cells from the environment and permit monitoring of disease over time. In this chapter, we describe the establishment of a murine model for cryptococcosis and the subsequent collection of organs, tissues, and fluids for sampling. These samples may support novel diagnostic strategies and opportunities to monitor dissemination of the fungal cells throughout the host and propose new treatment options to combat disease.

Epidemiological trends and clinical outcomes of cryptococcosis in a medically insured population in the United States: a claims-based analysis from 2017 to 2019

Background

Emerging risk factors highlight the need for an updated understanding of cryptococcosis in the United States.

Objective

Describe the epidemiological trends and clinical outcomes of cryptococcosis in three patient groups: people with HIV (PWH), non-HIV-infected and non-transplant (NHNT) patients, and patients with a history of solid organ transplantation.

Methods

We utilized data from the Merative Medicaid Database to identify individuals aged 18 and above with cryptococcosis based on the International Classification of Diseases, Tenth Revision diagnosis codes from January 2017 to December 2019. Patients were stratified into PWH, NHNT patients, and transplant recipients according to Infectious Diseases Society of America guidelines. Baseline characteristics, types of cryptococcosis, hospitalization details, and in-hospital mortality rates were compared across groups.

Results

Among 703 patients, 59.7% were PWH, 35.6% were NHNT, and 4.7% were transplant recipients. PWH were more likely to be younger, male, identify as Black, and have fewer comorbidities than patients in the NHNT and transplant groups. Notably, 24% of NHNT patients lacked comorbidities. Central nervous system, pulmonary, and disseminated cryptococcosis were most common overall (60%, 14%, and 11%, respectively). The incidence of cryptococcosis fluctuated throughout the study period. PWH accounted for over 50% of cases from June 2017 to June 2019, but this proportion decreased to 47% from July to December 2019. Among the 52% of patients requiring hospitalization, 61% were PWH and 35% were NHNT patients. PWH had longer hospital stays. In-hospital mortality at 90 days was significantly higher in NHNT patients (22%) compared to PWH (7%) and transplant recipients (0%). One-year mortality remained lowest among PWH (8%) compared to NHNT patients (22%) and transplant recipients (13%).

Conclusion

In this study, most cases of cryptococcosis were PWH. Interestingly, while the incidence remained relatively stable in PWH, it slightly increased in those without HIV by the end of the study period. Mortality was highest in NHNT patients.

Analytical and clinical validation of multiplex droplet digital PCR assay for detecting pathogenic fungal infection in lungs

Pulmonary invasive fungal infection in immunocompromised hosts is difficult to diagnose, and current tools for diagnosis or monitoring of response to antifungal treatments have inherent limitations. Droplet digital PCR (ddPCR) has emerged as a promising tool for pulmonary pathogen detection with high sensitivity. This study presents a novel ddPCR panel for rapid and sensitive identification of pulmonary fungal pathogens. First, a ddPCR method for detecting three fungal genera, including Pneumocystis, Aspergillus, and Cryptococcus, was established and evaluated. Then, the clinical validation performance of ddPCR was compared with that of qPCR using 170 specimens, and the 6 specimens with inconsistent results were further verified by metagenomics next-generation sequencing, which yielded results consistent with the ddPCR findings. Finally, the area under the ROC curve (AUC) was used to evaluate the efficiency of ddPCR. While the qPCR identified 16 (9.41%) cases of Aspergillus and 6 (3.53%) cases of Pneumocystis, ddPCR detected 20 (11.76%) Aspergillus cases and 8 (4.71%) Pneumocystis cases. The AUC for Aspergillus, Cryptococcus, and Pneumocystis was 0.974, 0.998, and 0.975, respectively. These findings demonstrated that the ddPCR assay is a highly sensitive method for identifying pathogens responsible for invasive fungal pulmonary infections, and is a promising tool for early diagnosis.      .

Cryptococcosis in kidney transplant recipients: Current understanding and practices

Cryptococcosis is the third most commonly occurring invasive fungal disease in solid organ transplant recipients (SOT). It is caused by encapsulated yeast, Cryptococcus species, predominantly Cryptococcus neoformans and Cryptococcus gattii. Though kidney transplant recipients are at the lowest risk of cryptococcosis when compared to other solid organ transplant recipients such as lung, liver or heart, still this opportunistic infection causes significant morbidity and mortality in this subset of patients. Mortality rates with cryptococcosis range from 10%-25%, while it can be as high as 50% in SOT recipients with central nervous system involvement. The main aim of diagnosis is to find out if there is any involvement of the central nervous system in disseminated disease or whether there is only localized pulmonary involvement as it has implications for both prognostication and treatment. Detection of cryptococcal antigen (CrAg) in cerebrospinal fluid or plasma is a highly recommended test as it is more sensitive and specific than India ink and fungal cultures. The CrAg lateral flow assay is the single point of care test that can rapidly detect cryptococcal polysaccharide capsule. Treatment of cryptococcosis is challenging in kidney transplant recipients. Apart from the reduction or optimization of immunosuppression, lipid formulations of amphotericin B are preferred as induction antifungal agents. Consolidation and maintenance are done with fluconazole; carefully monitoring its interactions with calcineurin inhibitors. This review further discusses in depth the evolving developments in the epidemiology, pathogenesis, diagnostic assays, and management approach of cryptococcosis in kidney transplant recipients.

A Case of S1Q3T3-A Classic Nonspecific Electrocardiogram Finding

This case report describes a patient in their 40s with a history of end-stage kidney disease secondary to hypertension and diabetes who presented with fatigue, cough, weakness, and dyspnea on exertion and was subsequently diagnosed with acute disseminated cryptococcal infection.

Endobronchial cryptococcosis with bronchial stenosis in a patient with severe asthma treated with inhaled corticosteroids: A case report

Cryptococcosis typically manifests as pulmonary lesions, with endobronchial lesions occurring rarely. Inhaled corticosteroids (ICS) may be a risk factor for cryptococcosis of the larynx but not of the bronchi. Here, we report a case involving a 73-year-old Japanese man who developed endobronchial cryptococcosis during ICS treatment for asthma. Chest computed tomography showed right mainstem bronchial stenosis and asthma control worsening when he received adequate asthma treatments. Bronchoscopy revealed multiple elevated lesions with white slough from the trachea to the right mainstem bronchus and the right mainstem bronchus lumen entrance narrowing. Bronchial lavage culture revealed Cryptococcus neoformans. Combination treatment with the antifungal agent, mepolizumab, and bronchodilation surgery successfully controlled cryptococcosis and asthma. Attention should be paid to central airway lesions during ICS treatment for uncontrolled asthma.

Evaluation of pulmonary abnormalities in recipients of hematopoietic cell transplants and cellular therapies

Hematopoietic cell transplant (HCT) and chimeric antigen receptor T-cell (CAR-T) therapy recipients are susceptible to multiple pulmonary complications that are caused by infectious and noninfectious processes. Numerous variables can be associated with specific pulmonary diseases including time from transplantation, presence of graft versus host disease (GVHD), underlying disease, and prolonged neutropenia and lymphocytopenia. Most pulmonary complications are infectious in origin, with bacterial pneumonia remaining the most common pulmonary infection, particularly before neutrophil engraftment. Invasive fungal infections continue to affect this patient population even when antifungal prophylaxis is used. Noninfectious pulmonary complications include a wide differential of pathologies in this population, and as clinical presentations of these various pulmonary disorders often overlap, clinicians frequently will use a multidisciplinary approach in diagnosing these abnormalities. Radiography, particularly with chest computed tomography (CT) imaging, is an essential tool in identifying pulmonary pathology and potential sources. While standard microbiological cultures of respiratory specimens are still utilized, their role is limited by low sensitivity and diagnostic yield. The likelihood of obtaining a diagnosis can be improved by using other microbiological assays, including fungal antigen tests and molecular diagnostic methods, particularly if specimens are collected via bronchoscopy. This review will highlight the more common causes of pulmonary diseases encountered after HCT and CAR-T and will examine the different methods in their diagnosis.

Cryptococcus neoformans presenting as a large pulmonary cavitary lesion in an immunocompetent female

Pulmonary cryptococcus is a rare but fatal fungal infection historically associated with Human Immunodeficiency Virus (HIV) and immunosuppression, yet increasingly also being recognized in immunocompetent patients as a result of antiretroviral therapy and improved HIV control reducing HIV-associated cryptococcus in advanced countries. Appropriate management may be delayed if left unrecognized. We present the case of an immunocompetent middle-aged female with nonspecific respiratory symptoms who was found to have a large cavitary lung mass resulting in external compression of the pulmonary vein, ultimately leading to a diagnosis of pulmonary Cryptococcus neoformans. By presenting this case, we hope to elucidate the challenges in diagnosing and managing this fatal disease in timely fashion.

Pulmonary cryptococcosis closely mimicking lung cancer in a membranous nephropathy patient taking calcineurin inhibitor

In patients with membranous nephropathy (MN), malignancy may be either the underlying disease or results of immunosuppressive therapy which may also lead to opportunistic infections including the pulmonary cryptococcosis. On CT scan, nodule is the most common feature in pulmonary cryptococcosis and it can mimic lung cancer both clinically and radiologically. Therefore, pulmonary nodular lesions caused by cryptococcosis may be easily misdiagnosed and require unnecessary surgical treatment. As such, we herein presented an isolated subpleural solitary nodule with satellite lesion that closely mimicked lung cancer on both contrast-enhanced computed tomography (CT) scan and 18F-fluorodeoxyglucose positron emission tomography (FDG-PET)/CT in an MN patient under long-term tacrolimus regimen. Cryptococcosis was ascertained by the finding of oval thick-walled yeast on histopathology of the lung biopsy specimen taken during the Argon-Helium cryotherapy. Further, the pulmonary lesions progressively dissipated after antifungal treatment. Arguably, our experience may help clinicians in general and nephrologists in particular with a better understanding of the cryptococcal infection manifesting as pulmonary nodule(s) in the MN patients and contribute to more efficacious differential diagnosis against the lung cancer.