An official American Thoracic Society statement: Treatment of fungal infections in adult pulmonary and critical care patients

Fungal infections in intensive care unit: challenges in diagnosis and management

Infections have almost become an inseparable part of the intensive care units throughout the globe in spite of numerous advancements in diagnostic and therapeutic interventions. With advances in critical care medicine and introduction of broad-spectrum antibiotics, the incidence of invasive fungal infections in intensive care is on the rise, especially in patients with immunosuppression. The aim of this review is to collect recent information about various types of invasive fungal infections prevalent in the intensive care unit, the problems in their diagnosis and recent trends in their management. A thorough literature search was made in PubMed and Google using the following keywords for our search: Invasive fungal infection, antifungal therapy in intensive care unit, candidiasis. The major fungi implicated worldwide are Candida and Aspergillus spp., followed by Cryptococcus, Histoplasma, etc., in endemic areas. These produce a wide variety of infections that are difficult to diagnose as most of the diagnosing tests are non-specific and the culture takes a long time. An early suspicion of fungal infection with institution of appropriate antifungal therapy is mandatory for a positive outcome and to prevent development of invasive fungal infection.

Evaluation of human body fluids for the diagnosis of fungal infections

Invasive fungal infections are a major cause of morbidity and mortality in immunocompromised patients. Because the etiologic agents of these infections are abundant in nature, their isolation from biopsy material or sterile body fluids is needed to document infection. This review evaluates and discusses different human body fluids used to diagnose fungal infections.

Aspergillus-associated airway disease, inflammation, and the innate immune response

Aspergillus moulds exist ubiquitously as spores that are inhaled in large numbers daily. Whilst most are removed by anatomical barriers, disease may occur in certain circumstances. Depending on the underlying state of the human immune system, clinical consequences can ensue ranging from an excessive immune response during allergic bronchopulmonary aspergillosis to the formation of an aspergilloma in the immunocompetent state. The severest infections occur in those who are immunocompromised where invasive pulmonary aspergillosis results in high mortality rates. The diagnosis of Aspergillus-associated pulmonary disease is based on clinical, radiological, and immunological testing. An understanding of the innate and inflammatory consequences of exposure to Aspergillus species is critical in accounting for disease manifestations and preventing sequelae. The major components of the innate immune system involved in recognition and removal of the fungus include phagocytosis, antimicrobial peptide production, and recognition by pattern recognition receptors. The cytokine response is also critical facilitating cell-to-cell communication and promoting the initiation, maintenance, and resolution of the host response. In the following review, we discuss the above areas with a focus on the innate and inflammatory response to airway Aspergillus exposure and how these responses may be modulated for therapeutic benefit.

Antifungal Activity of Leaves of Mangroves Plant Acanthus licifolius Against Aspergillus fumigatus

The antifungal activity of chloroform extract of leaves of Acanthus ilicifolius was evaluated in Aspergillus fumigatus infected mice. Swiss albino mice (60) were divided into five groups. All the groups were immunosuppressed with cyclophosphamide and cortisone acetate couple of days prior to intranasal inoculation with Aspergillus fumigatus conidia (10⁶) in all the groups, except the first. Treatment was initiated at 24 h of fungal inoculation and continued up to day 14, and included amphotericin B (1 mg/kg orally) for group III and extract of Acanthus ilicifolius at 250 mg and 500 mg/kg for group IV and V, respectively. Groups I and II received sterile water orally for the same period. From each group, three mice were sacrificed after 1 h and the remaining mice on the 14^th day of inoculation. One hour post-inoculation lung colony forming unit count confirmed the delivery of conidia into the lungs. Colony forming unit count, intensity of gross necropsy changes and histopathological changes were highest in group II. It improved in group III and also in groups IV and V in dose-dependent manner. Lesions were absent in the noninfected group. Lesions included maximum granulomatous inflammation of lung, multifocal diffused necrotic granulomas on kidney and moderate microgranulomas on liver. From this study, it was concluded that chloroform extract of Acanthus ilicifolius contains active principles that are absorbed after oral administration to produce systemic effects when given at 500 mg/kg dose.

[Antifungal treatment options in the critically ill patient]

Invasive fungal infections, especially in the critical care setting, have become an excellent target for prophylactic, empiric, and pre-emptive therapy interventions due to their associated high morbidity, mortality rate, increased incidence, and healthcare costs. For these reasons, new studies and laboratory tests have been developed over the last few years in order to formulate an early therapeutic intervention strategy in an attempt to reduce the high mortality rate associated with these infections. In recent years, evidence-based studies have shown the roles that the new antifungal drugs play in the treatment of invasive mycosis in seriously ill and complex patients, although data from critically ill patients are more limited. New antifungal agents have been analyzed in different clinical situations in critical care units, and the increasing number of non-Candida albicans species suggest that the application of early echinocandin therapy in critically ill patients with invasive candidiasis is a good option. Voriconazole should be recommended for invasive aspergillosis as a first line option.

Airway and parenchymal manifestations of pulmonary aspergillosis

Pulmonary aspergillosis encompasses a heterogeneous group of mycoses that result from either colonisation or pathogenic damage of lung tissue by Aspergillus fungi. These clinical entities range from relatively benign saprophytic hypersensitivity associated with fungal inhabitation to life threatening invasive disease. The diagnosis of pulmonary disorders related to Aspergillus is on the increase and it is more important than ever those both general and respiratory physicians have a good understanding of these disorders. This paper reviews the contemporary understanding of the clinical, radiographic and histopathological aspects of pulmonary aspergillosis.

Other HIV-associated pneumonias

The incidence, mortality, and epidemiology of human immunodeficiency virus (HIV)-associated pulmonary infections have changed as a result of effective antiretroviral and prophylaxis antimicrobial therapy. The clinical presentation, radiographic abnormalities, and treatment of pneumonia from various uncommon pathogens in patients with AIDS can be different from those in immunocompetent patients. Advances in invasive and noninvasive testing and molecular biological techniques have improved the diagnosis and prognosis of pulmonary infections in patients infected with HIV. This review focuses on pulmonary infections from nontuberculosis mycobacteria, cytomegalovirus, fungi (aspergillosis, cryptococcosis, endemic fungi), and parasites (toxoplasmosis), and uncommon bacterial pneumonia (nocardiosis, rhodococcosis) in these patients.

Surgery for other pulmonary fungal infections, Actinomyces, and Nocardia

Surgical participation in the management of fungal infections has changed since the advent of effective antimicrobials. Even so, a surgeon may be called on for a variety of reasons, depending on the specific fungal infection and the evolution of thoracic disease. Specific fungal infections are enumerated. Each organism, its clinical picture, and method of diagnosis are briefly described and the medical and surgical management of thoracic disease are discussed.

Pneumocystis pneumonia in a non-HIV patient on chronic corticosteroid therapy: a question of prophylaxis

A man in his late 50s with a history of membranoproliferative glomerulonephritis presented with fever and mild dyspnoea. He was HIV-negative and had been on corticosteroids as immunosuppression for 6 months prior to tapering them off 1 week before presentation. He was not taking prophylaxis for Pneumocystis jirovecii pneumonia. After unsuccessful treatment for community-acquired pneumonia, his condition worsened and he required intubation and mechanical ventilation. Full respiratory workup including bronchoscopy revealed P jirovecii as a source for the patient's infection. He was treated successfully with a 21-day course of trimethoprim-sulfamethoxazole  and eventually weaned off the ventilator. He has had no complications to date. In our review of this case and the existing literature, we believe that proper utilisation of prophylaxis for pneumocystis pneumonia may have prevented our patient's transfer to intensive care unit. In our article, we discuss this issue and explore current evidence for prophylaxis.

Pulmonary fungal infections

This review details some of the advances that have been made in the recent decade in the diagnosis, treatment and epidemiology of pulmonary fungal infections. These advances have occurred because of increasing knowledge regarding the fungal genome, better understanding of the structures of the fungal cell wall and cell membrane and the use of molecular epidemiological techniques. The clinical implications of these advances are more rapid diagnosis and more effective and less toxic antifungal agents. For example, the diagnosis of invasive pulmonary aspergillosis, as well as histoplasmosis and blastomycosis, has improved with the use of easily performed antigen detection systems in serum and bronchoalveolar lavage fluid. Treatment of angioinvasive moulds has improved with the introduction of the new azoles, voriconazole and posaconazole that have broad antifungal activity. Amphotericin B is less frequently used, and when used is often given as lipid formulation to decrease toxicity. The newest agents, the echinocandins, are especially safe as they interfere with the metabolism of the fungal cell wall, a structure not shared with humans cells. Epidemiological advances include the description of the emergence of Cryptococcus gattii in North America and the increase in pulmonary mucormycosis and pneumonia due to Fusarium and Scedosporium species in transplant recipients and patients with haematological malignancies. The emergence of azole resistance among Aspergillus species is especially worrisome and is likely related to increased azole use for treatment of patients, but also to agricultural use of azoles as fungicides in certain countries.

Pulmonary sporotrichosis: case series and systematic analysis of literature on clinico-radiological patterns and management outcomes

Pulmonary infections by Sporothrix spp. manifest radiologically as cavitary or non-cavitary disease depending on whether the infection is primary pulmonary or multifocal sporotrichosis. Despite current guidelines, the optimal management for pulmonary sporotrichosis remains unclear. In order to clarify this, we present two cases of pulmonary sporotrichosis, as well as the results of a comprehensive literature review of treatment outcomes based on clinico-radiological presentation patterns of the disease. A literature search of all case reports in English language over the last 50 years (1960-2010) was conducted. Data on patient characteristics, risk factors, clinico-radiological patterns, treatment modalities and outcomes were collected and analyzed. A total of 86 cases were identified, i.e., 64 (74.4%) primary pulmonary and 22 (25.6%) multifocal sporotrichosis. Radiologically, primary pulmonary disease was commonly characterized by cavity formation which was lacking in multifocal infections (P = 0.0001). Immunosuppressant use was more common in multifocal sporotrichosis (P = 0.0001), while hemoptysis was more common in primary pulmonary form (P = 0.01). No other differences in patient characteristics or risk factors were noted. Extra-pulmonary multifocal sporotrichosis most commonly involved skin (81.8%) and joints (45.4%). For patients with cavitary primary pulmonary sporotrichosis, outcomes from medical therapy alone were inferior to surgical intervention (P = 0.02). However, for both primary pulmonary and multifocal sporotrichosis with non-cavitary disease, medical therapy alone provided good outcomes. Only 12 (16.7%) cases were treated with itraconazole. Treatment of pulmonary sporotrichosis should be guided by the clinico-radiological patterns of presentation. Medical therapy alone is likely sufficient for non-cavitary disease while early surgery should be considered for cavitary primary pulmonary sporotrichosis. The experience in treating cavitary disease with itraconazole alone is limited and further data are required.

Disseminated histoplasmosis

Disseminated histoplasmosis is a relentlessly progressive granulomatous disease which can mimic many other granulomatous diseases including tuberculosis. A 48-year-old male was referred to us with 11 months history of multiple subcutaneous swellings and ulcerations over the upper and lower limbs and fever for 2 months. He was evaluated outside for several months and received anti tubercular drugs for about 2 years in the past for a granulomatous infection of bone and soft tissue identified by various biopsies, without any improvement. When he was evaluated and fresh biopsies were taken, they were stained for fungus and disseminated histoplasmosis was detected. This case confirms the importance of considering fungal infections as a possibility while treating disseminated granulomatous infections, even in immune-competent patients, especially if response to treatment is inadequate.

Histoplasmosis: a new endemic fungal infection in China? Review and analysis of cases

Histoplasmosis occurs in specific endemic areas, including the mid-western United States, Africa and most of Latin America. Sporadic cases have also been reported in China. The aim of this study was to summarise the epidemiological and clinical data of histoplasmosis in China. We searched the PubMed, CBMdisk and CNKI databases to identify publications related to histoplasmosis in China. Case reports/series on patients with histoplasmosis were included. A comprehensive literature review identified additional cases. The relevant material was evaluated and reviewed. Overall, 300 cases of histoplasmosis were reported in China from 1990 to 2011, and 75% were from regions through which the Yangtze River flows. Most of the patients were autochthonous infections. Of these, 43 patients had pulmonary histoplasmosis and 257 patients had disseminated histoplasmosis. Common underlying diseases included HIV infection, diabetes mellitus and liver diseases. Fever was the most frequently reported clinical feature in disseminated histoplasmosis, followed by splenomegaly and hepatomegaly. Cases of histoplasmosis had a prominent geographical distribution in China. Histoplasmosis should be considered in the diagnosis of patients with relevant symptoms and a history of travel to or residence in these areas.

Detection, identification, and distribution of fungi in bronchoalveolar lavage specimens by use of multilocus PCR coupled with electrospray ionization/mass spectrometry

As pulmonary fungal infections continue to increase due to an increasing number of immunocompromised patients, rapid detection and accurate identification of these fungal pathogens are critical. A broad fungal assay was developed by incorporating broad-range multilocus PCR amplification and electrospray ionization/mass spectrometry (PCR/ESI-MS) to detect and identify fungal organisms directly from clinical specimens. The aims of this study were to evaluate the performance of PCR/ESI-MS for detection, identification, and determination of the distribution of fungal organisms in bronchoalveolar lavage (BAL) fluid specimens. The BAL fluid specimens submitted for fungal culture at Vanderbilt University Medical Center between May 2005 and October 2011 were included. Cultures and identification were done using standard procedures. In addition, DNA was extracted from BAL fluid specimens, and fungal DNA amplification/identification were performed by PCR/ESI-MS. The results were compared with those of the standard cultures. A total of 691 nonduplicated BAL fluid specimens with sufficient leftover volume for molecular testing were evaluated using PCR/ESI-MS. Among them, 134 specimens (19.4%) were positive for fungi by both culture and PCR/ESI-MS testing. Of the dual-positive specimens, 125 (93.3%) were positive for Candida and Aspergillus species, with concordances between culture and PCR/ESI-MS results being 84 (67.2%) at the species level and 109 (87.2%) at the genus level. In addition, 243 (35.2%) and 30 (4.3%) specimens were positive only by PCR/ESI-MS or by culture, respectively (odds ratio [OR] = 11.95, 95% confidence interval [CI] = 7.90 to 18.17, P = 0.0000). Codetection of fungal organisms was noted in 23 (3.3%) specimens by PCR/ESI-MS, which was significantly higher than the 4 (0.6%) in which they were noted by culture (OR = 5.91, 95% CI = 1.93 to 20.27, P = 0.0002). Among 53 specimens in which cultures failed because of bacterial overgrowth, at least one fungus was identified in 26 specimens (47.3%) by PCR/ESI-MS. PCR/ESI-MS provides an advanced tool for rapid and sensitive detection, identification, and determination of the distribution of fungal organisms directly from BAL fluid specimens. Moreover, it detected fungal organisms in specimens in which cultures failed because of bacterial overgrowth. The clinical relevance of the significantly higher detection rate of fungal organisms by PCR/ESI-MS merits further investigation.

Detection of (1, 3)-β-D-glucan in bronchoalveolar lavage and serum samples collected from immunocompromised hosts

The incidence of invasive fungal infections (IFI) has increased in recent years, especially among immunocompromised hosts (ICH). In 2003, the Fungitell(®) assay received FDA clearance for the presumptive diagnosis of IFI using serum and detects (1-3)-β-D-glucan, which is a major cell wall component of certain fungi (e.g., Candida, Aspergillus, and Pneumocystis). The goal of the current study was to assess the performance of the assay on bronchoalveolar lavage (BAL) fluid and serum to identify IFI in ICH. Patients were classified as having proven, probable, possible, or no IFI according to the European Organization for Research and Treatment of Cancer/Mycoses Study Group (EORTC/MSG) guidelines. Among 109 patients for whom the results of Fungitell were compared to the EORTC/MSG criteria, Fungitell showed a low positive predictive value for the identification of IFI from both BAL (20.0%) and serum (26.7%). However, the negative predictive value of Fungitell was significantly higher for both sample types (BAL, 83.0%; serum, 84.8%). Interestingly, the results of Fungitell were positive in BAL and serum in 7/8 (87.5%) patients diagnosed with Pneumocystis pneumonia (PcP) by real-time, non-nested PCR. These data indicate that the Fungitell assay has a low positive predictive value for the diagnosis of IFI in ICH, regardless of the specimen type that is tested. However, testing of serum samples by Fungitell may permit a rapid and noninvasive initial screening approach in patients with presumed PcP.

Systemic dissemination of chronic necrotizing pulmonary aspergillosis in an elderly woman without comorbidity: a case report

Introduction

Chronic necrotizing pulmonary aspergillosis usually occurs in mildly immune-compromised hosts or those with underlying pulmonary disease. The radiographic pattern of chronic necrotizing pulmonary aspergillosis is typically a progressive upper lobe cavitary infiltrate with pleural thickening. We report here an atypical case of chronic necrotizing pulmonary aspergillosis mimicking lung cancer, which developed into a disseminated fatal disease in an older woman with no comorbidity.

Case presentation

An 80-year-old Japanese woman was referred to our hospital for a chest roentgenogram abnormality. Repeated fiber-optic bronchoscopy could not confirm any definite diagnosis, and she refused further examinations. Considering the roentgenogram findings and her age, she was followed-up as a suspected case of lung cancer without any treatment. Then, 10 months later, she complained of visual disturbance and was admitted to our department of ophthalmology. She was diagnosed as having endophthalmitis. After treatment with corticosteroids for 20 days, she developed acute encephalitis and died four weeks later. Autopsy revealed dissemination of Aspergillus hyphae throughout her body, including her brain.

Conclusions

In older patients, even if they do not have any comorbidity, chronic necrotizing pulmonary aspergillosis should be added to the differential diagnosis of solitary pulmonary lesions in a chest roentgenogram.

Human herpes virus co-infection is associated with mortality in HIV-negative patients with Pneumocystis jirovecii pneumonia

The purpose of this investigation was to characterize the management and prognosis of severe Pneumocystis jirovecii pneumonia (PJP) in human immunodeficiency virus (HIV)-negative patients. An observational cohort study of HIV-negative adults with PJP documented by bronchoalveolar lavage (BAL) through Gomori-Grocott staining or immunofluorescence, admitted to one intensive care unit (ICU) for acute respiratory failure, was undertaken. From 1990 to 2010, 70 patients (24 females, 46 males) were included, with a mean age of 58.6 ± 18.3 years. The mean Simplified Acute Physiology Score (SAPS)-II was 36.9 ± 20.4. Underlying conditions included hematologic malignancies (n = 21), vasculitis (n = 13), and solid tumors (n = 13). Most patients were receiving systemic corticosteroids (n = 63) and cytotoxic drugs (n = 51). Not a single patient received trimethoprim-sulfamethoxazole as PJP prophylaxis. Endotracheal intubation (ETI) was required in 42 patients (60.0 %), including 38 with acute respiratory distress syndrome (ARDS). In-ICU mortality was 52.9 % overall, reaching 80.9 % and 86.8 %, respectively, for patients who required ETI and for patients with ARDS. In the univariate analysis, in-ICU mortality was associated with SAPS-II (p = 0.0131), ARDS (p < 0.0001), shock (p < 0.0001), and herpes simplex virus (HSV) or cytomegalovirus (CMV) on BAL (p = 0.0031). In the multivariate analysis, only ARDS was associated with in-ICU mortality (odds ratio [OR] 23.4 [4.5-121.9], p < 0.0001). PJP in non-HIV patients remains a serious disease with high in-hospital mortality. Pulmonary co-infection with HSV or CMV may contribute to fatal outcome.

Immunocompromised Patients

The ominous prognosis of cancer patients with or without neutropenia in need of critical care has led to reservations with regard to admission of cancer patients to the ICU. However, significant improvements in ICU and in-hospital survival of cancer patients in ICU have been demonstrated in studies in recent years [1–4]. Risk factors for mortality have shifted from those related to the underlying condition to those related to the severity of acute illness similar to other critically-ill patients. Neutropenia per se and the underlying malignancy (solid and hematological) do not have an impact on the outcome of patients in ICU. Recent chemotherapy is associated rather with improved survival [3, 5–7], while organ dysfunction, severity of disease scores, need for vasopressor treatment, need for mechanical ventilation immediately or after noninvasive ventilation, no definite diagnosis and a non-infectious diagnosis are associated with mortality [1–3, 8]. Invasive aspergillosis is also associated with very high mortality rates in ICU (see below). In several studies, admission to ICU in the early stages of sepsis or other acute event was associated with better survival than admission later, after development of organ dysfunction. Performance status is perhaps the most important and only variable relating to the underlying condition that is correlated with ICU death. The prognosis remains guarded for certain cancer patients, including patients after allogeneic hematopoietic stem cell transplantation (HSCT) with active uncontrolled graft versus host disease, those with relapse of the primary disease after allogeneic HSCT and special cases of solid cancer including pulmonary carcinomatous lymphangitis and carcinomatous meningitis with coma [9].

Colonization by Pneumocystis jirovecii and its role in disease

Although the incidence of Pneumocystis pneumonia (PCP) has decreased since the introduction of combination antiretroviral therapy, it remains an important cause of disease in both HIV-infected and non-HIV-infected immunosuppressed populations. The epidemiology of PCP has shifted over the course of the HIV epidemic both from changes in HIV and PCP treatment and prevention and from changes in critical care medicine. Although less common in non-HIV-infected immunosuppressed patients, PCP is now more frequently seen due to the increasing numbers of organ transplants and development of novel immunotherapies. New diagnostic and treatment modalities are under investigation. The immune response is critical in preventing this disease but also results in lung damage, and future work may offer potential areas for vaccine development or immunomodulatory therapy. Colonization with Pneumocystis is an area of increasing clinical and research interest and may be important in development of lung diseases such as chronic obstructive pulmonary disease. In this review, we discuss current clinical and research topics in the study of Pneumocystis and highlight areas for future research.

Endemic mycoses: overlooked causes of community acquired pneumonia

The endemic mycoses are important but often overlooked causes for community acquired pneumonia. Delays in recognition, diagnosis and proper treatment often lead to disastrous outcomes. This topic is not usually discussed in reviews and guidelines addressing the subject of community acquired pneumonia. In this review we discuss the three major endemic mycoses in North America that present as community acquired pneumonias; Coccidioidomycosis, Histoplasmosis and Blastomycosis. We discuss their epidemiology, clinical presentations, methods of diagnosis and current treatment strategies.

Berberine and itraconazole are not synergistic in vitro against Aspergillus fumigatus isolated from clinical patients

The incidence of Aspergillus fumigatus infections has become more frequent as a consequence of widespread immunosuppression. At present, the number of available antifungal agents in the clinic is limited, and most of them, such as itraconazole (ICZ), are toxic and show resistance. Berberine (BER) is a plant alkaloid used in the clinic mainly for alimentary infections. We have used BER and ICZ to measure in vitro resistance in A. fumigatus isolated from clinical patients. The minimum inhibitory concentration ranges of BER and ICZ were 4–256 and 0.031–0.250 μg/mL, respectively. In addition, against A. fumigatus IFM 40808 strain, the MIC₅₀ values of BER and ICZ were 8 and 0.125 μg/mL. Using this strain, we compared the giant colonies with or without BER, and concluded that BER could restrain A. fumigatus mycelial growth and conidial pigment production. Combinations of the two drugs were also tested by the checkerboard assay to identify any functional interactions between them. Thirty-two out of 42 isolates had FICI values > 4.0, indicating that two drugs were mutually antagonistic. In conclusion, it is not advised that BER and ICZ be used in the clinic at the same time. Our results indicated that BER may inhibit A. fumigatus through the ergosterol biosynthesis pathway, like ICZ.

Pulmonary aspergillosis: a clinical review

Aspergillus is a mould which may lead to a variety of infectious, allergic diseases depending on the host's immune status or pulmonary structure. Invasive pulmonary aspergillosis occurs primarily in patients with severe immunodeficiency. The significance of this infection has dramatically increased with growing numbers of patients with impaired immune state associated with the management of malignancy, organ transplantation, autoimmune and inflammatory conditions; critically ill patients and those with chronic obstructive pulmonary disease appear to be at an increased risk. The introduction of new noninvasive tests, combined with more effective and better-tolerated antifungal agents, has resulted in lower mortality rates associated with this infection. Chronic necrotising aspergillosis is a locally invasive disease described in patients with chronic lung disease or mild immunodeficiency. Aspergilloma is usually found in patients with previously formed cavities in the lung, whereas allergic bronchopulmonary aspergillosis, a hypersensitivity reaction to Aspergillus antigens, is generally seen in patients with atopy, asthma or cystic fibrosis. This review provides an update on the evolving epidemiology and risk factors of the major manifestations of Aspergillus lung disease and the clinical manifestations that should prompt the clinician to consider these conditions. Current approaches for the diagnosis and management of these syndromes are discussed.