The spectrum of pulmonary cryptococcosis

Pleural cryptococcosis diagnosed by pleural biopsy in an immunocompromised patient: a case report

Objective

The aim of this study is to report an isolated pleural cryptococcosis with pleural effusion as the only manifestation, confirmed by pleural biopsy in a patient with thymoma combined with myasthenia gravis, who developed pleural effusion of unknown origin after long-term glucocorticoids and tacrolimus therapy.

Methods

Pathological examination of the right pleural biopsy tissue from a patient with unexplained recurrent pleural effusion was implemented. Morphological analysis of the fungal component and metagenomic next-generation sequencing (mNGS) on the pleural tissue were performed.

Results

A biopsy specimen of the right pleura revealed numerous yeast-like organisms surrounded by mucous capsules and Cryptococcus neoformans was detected by mNGS with a species-specific read number (SSRN) of 4, confirming the diagnosis of pleural cryptococcosis. Pleural effusion was eliminated with amphotericin B and fluconazole, and healthy status was maintained at the time of review 1 year later.

Conclusion

Cryptococcosis, manifested by simple pleural effusion, is extremely rare, but when repeated pleural effusion occurs in immunocompromised patients or in patients with malignant tumors, the possibility of cryptococcosis should be treated with high vigilance and pleural biopsy is recommended if necessary in order to confirm the diagnosis.

Cerebellitis associated with cryptococcal-immune reconstitution inflammatory syndrome

Cerebellitis associated with cryptococcal immune reconstitution inflammatory syndrome (IRIS) has not been previously reported. We describe a unique case of IRIS associated cerebellitis in an AIDS patient with cryptococcosis.

Fun with fungi: a comprehensive review of common fungal organisms encountered in cytology

The ability to detect and diagnose infection is essential in the practice of cytopathology. The identification of suppurative or granulomatous inflammation should prompt careful evaluation for infection. Many of the most commonly encountered fungal organisms demonstrate characteristic microscopic appearances that allow accurate identification even with routine cytology stains, particularly when considered in the context of clinical factors such as geographic location, social history, patient immune status, and symptoms. Given the vital role cytopathologists play in the accurate diagnosis or presumptive identification of infections, this review explores the epidemiology, clinical manifestations, and morphologic features of common fungal pathogens in addition to their differential diagnoses and ancillary testing methods.

An Immunogenic and Slow-Growing Cryptococcal Strain Induces a Chronic Granulomatous Infection in Murine Lungs

Many successful pathogens cause latent infections, remaining dormant within the host for years but retaining the ability to reactivate to cause symptomatic disease. The human opportunistic fungal pathogen Cryptococcus neoformans establishes latent pulmonary infections in immunocompetent individuals upon inhalation from the environment. These latent infections are frequently characterized by granulomas, or foci of chronic inflammation, that contain dormant and persistent cryptococcal cells. Immunosuppression can cause these granulomas to break down and release fungal cells that proliferate, disseminate, and eventually cause lethal cryptococcosis. This course of fungal latency and reactivation is understudied due to limited models, as chronic pulmonary granulomas do not typically form in mouse cryptococcal infections. A loss-of-function mutation in the Cryptococcus-specific MAR1 gene was previously described to alter cell surface remodeling in response to host signals. Here, we demonstrate that the mar1Δ mutant strain persists long term in a murine inhalation model of cryptococcosis, inducing a chronic pulmonary granulomatous response. We find that murine infections with the mar1Δ mutant strain are characterized by reduced fungal burden, likely due to the low growth rate of the mar1Δ mutant strain at physiological temperature, and an altered host immune response, likely due to inability of the mar1Δ mutant strain to properly employ virulence factors. We propose that this combination of features in the mar1Δ mutant strain collectively promotes the induction of a more chronic inflammatory response and enables long-term fungal persistence within these granulomatous regions.

Atypical Radiographic Presentation of Cryptococcus Pneumonia in a Newly Diagnosed HIV Patient

Background

Cryptococcus infection is an opportunistic infection that occurs primarily among immunocompromised patients, and the morbidity and mortality of this infection is high if left unrecognized and untreated. There are no clinical or radiographic characteristics typical of cryptococcal pneumonia, and its clinical and radiological presentations often overlap with other diagnoses.

Case Presentation

We present a case of a 25-year-old man from Ghana admitted for an altered mental state, weight loss, neck pain, fever, and photophobia. He was diagnosed with Cryptococcus neoformans meningitis by cerebrospinal fluid culture and with disseminated cryptococcal infection by a positive Cryptococcus blood test. Diffuse micronodular opacities were found in a miliary pattern in the upper portions of both lungs upon imaging, which suggested miliary tuberculosis; thus, the patient was started on antituberculosis therapy. The patient underwent flexible fiber optic bronchoscopy, and transbronchial biopsy of the right lung showed bronchopneumonia with fungal spores consistent with filamentous Cryptococcus neoformans, which grew in tissue culture of the right lung. Interferon-gamma release assay, Mycobacterium tuberculosis PCR, and acid-fast bacilli staining of the bronchoalveolar lavage were negative for the M. tuberculosis complex.

Conclusion

The similarities in clinical and imaging findings among patients with acute immunodeficiency syndrome with coinfections make diagnoses difficult; thus image-guided biopsies are essential to confirm diagnoses.

Cryptococcosis

Cryptococcosis is an invasive mycosis caused by pathogenic encapsulated yeasts in the genus Cryptococcus. Cryptococcus gained prominence as a pathogen capable of widespread disease outbreaks in vulnerable populations. We have gained insight into the pathobiology of Cryptococcus, including the yeast' s capacity to adapt to environmental pressures, exploit new geographic environments, and cause disease in both immunocompromised and apparently immunocompetent hosts. Inexpensive, point-of-care testing makes diagnosis more feasible than ever. The associated worldwide burden and mortality remains unacceptably high. Novel screening strategies and preemptive therapy offer promise at making a sustained and much needed impact on this sugar-coated opportunistic mycosis.

Pulmonary Cryptococcosis in the Immunocompetent Patient-Many Questions, Some Answers

Background. There are no prospective data regarding the management of pulmonary cryptococcosis in the immunocompetent patient. Clinical guidelines recommend oral fluconazole for patients with mild to moderate symptoms and amphotericin B plus flucytosine followed by fluconazole for severe disease. It is unclear whether patients who have histological evidence of Cryptococcus neoformans but negative cultures will even respond to drug treatment. We evaluated and managed a patient whose presentation and course raised important questions regarding the significance of negative cultures, antifungal choices, duration of therapy, and resolution of clinical, serologic, and radiographic findings.

Methods. In addition to our experience, to answer these questions we reviewed available case reports and case series regarding immunocompetent patients with pulmonary cryptococcosis for the last 55 years using the following definitions: Definite - Clinical and/or radiographic findings of pulmonary infection and respiratory tract isolation of C. neoformans without other suspected etiologies; Probable - Clinical and radiographic findings of pulmonary infection, histopathologic evidence of C. neoformans, and negative fungal cultures with or without a positive cryptococcal polysaccharide antigen.

Results. Pulmonary cryptococcosis resolves in most patients with or without specific antifungal therapy. Clinical, radiographic, and serologic resolution is slow and may take years.

Conclusions. Persistently positive antigen titers are most common in untreated patients and may remain strongly positive despite complete or partial resolution of disease. Respiratory fungal cultures are often negative and may indicate nonviable organisms.

Cryptococcosis

Cryptococcosis is an infectious disease caused by the encapsulated fungi Cryptococcus neoformans and Cryptococcus gattii. Once a relatively uncommon cause of human disease, cryptococcal infection can develop in apparently immunocompetent hosts and has emerged as an important opportunistic infection in humans over the past several decades as immunocompromised populations expand in the setting of HIV/AIDS, organ transplantation, malignancies, and treatment for other conditions. Clinical manifestations are myriad but pulmonary and central nervous system (CNS) infections are the most common. Improvements in diagnostic testing and standardized approaches to antifungal therapy, when available, have made considerable impact in the management of this infection. While the widespread use of highly active antiretroviral therapy (HAART) has improved the outcome of cryptococcosis in many HIV-infected patients, cryptococcosis remains an entity of considerable morbidity and mortality in many parts of the world, and restoration of host immunity can present management challenges that require individualized management. As immunocompromised populations continue to expand, it is likely that cryptococcosis will remain an important opportunistic fungal infection of humans requiring ongoing investigation.

Increased chitinase expression and fungal-specific antibodies in the bronchoalveolar lavage fluid of asthmatic children

BACKGROUND

Increasing evidence highlights the contribution of chitinases and fungal infection to the development of asthma.

OBJECTIVE

The purpose of this study was to characterize chitinase expression and serological markers of fungal infection in children with severe asthma.

METHODS

Bronchoalveolar lavage fluid (BALF) was collected from children undergoing clinically indicated flexible bronchoscopy. A diagnosis of asthma was confirmed by pulmonary function testing. BALF was tested for chitinase activity and YKL-40 (an enzymatically inactive chitinase) concentrations. Specimens were cultured for fungal organisms and tested for cryptococcal antigen by ELISA. IgG and IgA reactivity to whole extract fungal (Aspergillus fumigatus, Alternaria alternata, Cryptococcus neoformans and Candida albicans) proteins were determined by immunoblot assay.

RESULTS

Among the 37 patients studied, 30 were asthmatic and 7 were non-asthmatic. Asthmatics exhibited elevated serum IgE levels (median: 748 IU/mL, IQR: 219-1765 IU/mL). Chitinase activity was greater in the BALF of asthmatics (mean, 0.85 ± 1.2 U/mL) compared with non-asthmatics (mean: 0.23 ± 0.21 U/mL, P = 0.012). Likewise YKL-40 concentrations were higher in the BALF of asthmatics and correlated with chitinase activity. There was a trend towards increased fungal-specific IgG in the BALF of asthmatics compared with non-asthmatics and for C. albicans this difference reached statistical significance. IgA reactivity to C. neoformans and A. fumigatus was greater in the BALF of asthmatics compared with non-asthmatics.

CONCLUSIONS AND CLINICAL RELEVANCE

Compared with non-asthmatics, asthmatic children exhibited increased chitinase activity and increased YKL-40 levels in BALF. Increased IgG and IgA reactivity to fungal proteins in the BALF of asthmatics may reflect a local response to fungal infection. Our findings are consistent with and suggest a role for chitinases in asthma pathogenesis among Bronx children and provide serological evidence of an association between fungal infection and severe asthma.

Cryptococcosis

In the past 2 decades, Cryptococcus has emerged in its clinical significance and as a model yeast for understanding molecular pathogenesis. C neoformans and C gattii are currently considered major primary and secondary pathogens in a wide array of hosts that are known to be immunocompromised or apparently immunocompetent. A recent outbreak of C gattii infections further underscores the clinical importance of the yeast through its epidemiology and pathogenicity features. With an enlarging immunosuppressed population caused by HIV infection, solid organ transplantation, and clinical use of potent immunosuppressives, such as cancer chemotherapy, monoclonal antibodies, and corticosteroids, this fungus has become a well-established infectious complication of modern medicine. This article examines current issues in cryptococcal infections, including new classification, epidemiology, pathogenesis, and specific clinical aspects.

A Dual Role For TGF-β1 in the Control and Persistence of Fungal Pneumonia

TGF-beta1 (TGF) has been implicated in the pathogenesis of several chronic infections and is thought to promote microbial persistence by interfering with macrophage function. In rats with experimental pulmonary cryptococcosis, increased lung levels of TGF were present at 12 mo of infection. Within the lung, expression of TGF localized to epithelioid cells and foamy macrophages in areas of inflammation. Increased TGF expression was also observed in the lungs of experimentally infected mice and a patient with pulmonary cryptococcosis. TGF reduced Ab and serum-mediated phagocytosis of Cryptococcus neoformans by rat alveolar macrophages (AM) and peripheral blood monocytes, and this was associated with decreased chemokine production and oxidative burst. Interestingly, TGF-treated rat AM limited both intracellular and extracellular growth of C. neoformans. Control of C. neoformans growth by TGF-treated rat AM was due to increased secretion of lysozyme, a protein with potent antifungal activity. The effects of TGF on the course of infection were dependent on the timing of TGF administration relative to the time of infection. TGF treatment of chronically infected rats resulted in reduced lung fungal burden, while treatment early in the course of infection resulted in increased fungal burden. In summary, our studies suggest a dual role for TGF in persistent fungal pneumonia whereby it contributes to the local control of infection by enhancing macrophage antifungal efficacy through increased lysozyme secretion, while limiting inflammation by inhibiting macrophage/monocyte phagocytosis and reducing associated chemokine production and oxidative burst.

Granuloma and cryptococcosis

This review describes the general histopathological features of cryptococcosis in immunocompetent individuals, as well as in patients with acquired immunodeficiency syndrome (AIDS). Details of the histological examination of cryptococcal lesions are described, with the consideration of morphological modifications induced by treatment with highly active antiretroviral therapy (HAART). The essential histological features of cryptococcosis in individuals with impaired T-cell functioning are yeast-cell proliferation with a histiocytic response, but only minor lymphocytic and neutrophilic components. Several histological patterns of pulmonary cryptococcal lesions are introduced in this article, some of which could be graded with respect to the degree and type of inflammatory reaction. One pattern was a mild lesion consisting of scattered small foci of intraalveolar cryptococcal proliferation with a histiocytic response. Another pattern involved massive cryptococcal infection, which may have been simply more extensive than that in the mild lesion. Capillary involvement of alveolar septa should be understood as an important common finding in patients with AIDS who had not been treated with HAART. In those patients, the absence of T cells and a decreasing function of antigen-presenting activity in histiocytes were confirmed by immunohistological examination. These findings suggest that the lungs of AIDS patients without HAART offer little resistance to bloodstream dissemination by cryptococci. The unique histological feature demonstrated in patients treated with HAART is characterized by the presence of CD4+ cells, greater response of histiocytes and multinucleated giant-cell formation, and lack of massive capillary involvement.

Cryptococcosis

Cryptococcus neoformans has risen to a worldwide highly recognizable major opportunistic pathogen with deadly consequences. It has become a model fungus to study a variety of paradigms in the host-fungus relationships. Genomic studies are advancing knowledge on its evolution and dissecting its virulence composite. Studies designed to understand host immunology to this fungus are leading to development of active and passive prevention and therapeutic strategies. This article collates and analyzes both new and old knowledge about the pathogen to help frame the meaning of human cryptococcosis as it starts to evolve in the new millennium.

Histopathology of cryptococcosis and other fungal infections in patients with acquired immunodeficiency syndrome

OBJECTIVE

To gain insight into the histopathologic characteristics of fungal infection in acquired immunodeficiency syndrome (AIDS).

METHODS

A review was conducted of the histopathology for 162 patients with evident fungal infection.

RESULTS

The microscopic appearance of esophageal candidiasis that was common in patients with single organ involvement revealed necrotic debris containing proliferating hyphae at the site of mucosal erosions without fungal invasion of underlying tissue. The incidence of oral and esophageal candidiasis was followed by that of pulmonary aspergillosis and Candida infection. Eighteen patients had generalized cryptococcosis, representing the commonest generalized fungal disease. The essential histologic features of the disease consisted of yeast cell proliferation with a histiocytic response, but only minor lymphocytic and neutrophilic components. This was different from the manifestations of both Candida and Aspergillus infections. The two histologic patterns recognized in the pulmonary cryptococcal lesions could be graded with respect to the degree and type of inflammatory reaction. The milder one consisted of small scattered foci of intra-alveolar cryptococcal proliferation with a histiocytic response. Another pattern involved massive cryptococcal infection, which might be simply more extensive than that in the former. Capillary involvement of alveolar septa was an important common finding in all 18 patients.

Pulmonary cryptococcosis in the immunocompetent host. Therapy with oral fluconazole: a report of four cases and a review of the literature

Isolated pulmonary cryptococcosis (IPC) is an infrequently diagnosed infection, the management of which is not well defined. In past years, IPC traditionally has not been treated in the immunocompetent host, given its perceived benign and self-limited course and the toxicity associated with amphotericin B. However, some patients manifest prominent and disabling symptoms, and infection occasionally may disseminate. Fluconazole is active against Cryptococcus neoformans, is easily administered, and has an excellent safety profile. We present four healthy hosts with IPC who were treated with oral fluconazole for 6 to 8 weeks. A review of the literature was conducted to identify other cases of IPC in healthy hosts who were also treated with fluconazole. Our results and the limited experience reported in the literature suggest that fluconazole may be an appropriate choice for the treatment of IPC in the immunocompetent host. Indications for treatment are not defined, but symptomatic patients, those with multiple nodules or extensive infiltrates on chest radiographs, and/or those testing positive for serum cryptococcal antigen might be potential candidates for therapy.

Intra-abdominal cryptococcosis in two dogs

Intra-abdominal cryptococcosis was diagnosed in two young dogs. The first, an entire male border collie, was presented with vomiting. An abdominal mass detected during physical examination proved to be cryptococcal mesenteric lymphadenitis on exploratory laparotomy. The second dog, a female neutered giant schnauzer, was presented with neurological signs suggestive of encephalopathy. Intestinal cryptococcal granulomas were detected in an extensive diagnostic investigation which included abdominal ultrasonography. The gastrointestinal tract was considered the most likely portal of entry for cryptococcal organisms in both cases. Both dogs were treated using surgery and multiagent antifungal chemotherapy. The first case succumbed despite therapy, while the second dog was treated successfully as gauged by return to clinical normality and a substantial decline in the cryptococcal antigen titre which continued to fall after cessation of treatment.

Cryptococcal pneumonia complicating pregnancy

In the present report we describe 4 previously healthy women who developed cryptococcal pneumonia during pregnancy, and 1 pregnant woman with cryptococcal meningitis. These cases illustrate a previously uncharacterized spectrum of cryptococcal disease. We also discuss 24 patients previously reported who had cryptococcal meningitis during pregnancy. Finally, we review the available data for each therapeutic option and present an algorithm for management based on appraisals of disease severity and risk to the unborn fetus. This report emphasizes the need for heightened awareness of cryptococcosis in the differential diagnosis of pneumonia, chest pain, and hypoxemia in the pregnant patient, but at present, there are insufficient epidemiologic data to determine whether incidences of pulmonary or disseminated cryptococcosis actually increase during pregnancy. The risk of congenital cryptococcosis to the unborn fetus is low, and the most likely mechanism whereby neonates acquire invasive fungal pulmonary infection is through aspiration. While it is unclear whether there is any real increased risk of spontaneous abortion or premature labor, the data indicate that overall fetal outcome depends on effective treatment of maternal infection. For patients with dense air-space consolidation, progressive pulmonary disease, or dissemination, antifungal therapy is necessary. Optimal treatment is determined by the acuity and severity of the clinical presentation. Amphotericin B (approximately 1 g) with or without flucytosine represents the choice for initial treatment of the more acutely ill patient with disseminated or progressive pulmonary cryptococcosis who requires hospitalization (whether during or after pregnancy). Oral fluconazole appears to be safe and effective alternative therapy after delivery for the less severely ill patient who can be managed on an outpatient basis. While the use of fluconazole during pregnancy generally appears safe in terms of fetal outcome (49, 58), the class C status and single report of fetal malformation (62) preclude confident recommendation for its use during pregnancy. The risks and benefits of this effective and generally less toxic drug should be discussed with the parents and weighed against the use of amphotericin B. For pregnant women with limited pulmonary cryptococcosis (segmental or nodular infiltrates) and no evidence of dissemination, we recommend close follow-up without antifungal therapy similar to the recommendation for normal hosts with minimal disease. However, it is important to note that there is no extensive experience upon which to base this recommendation for pregnant individuals (45, 55, 103, 108). It is prudent to use frequent physical examinations (for example, every 1-2 months), combined with chest roentgenograms and serum cryptococcal antigens to monitor progression and/or development of disease in both the mother and child for approximately 6 months postpartum. In conclusion, cryptococcosis during pregnancy presents a special challenge to the clinician. A balanced therapeutic approach holds great promise for successful maternal and fetal outcomes.

Cryptococcosis in the era of AIDS--100 years after the discovery of Cryptococcus neoformans

Although Cryptococcus neoformans and cryptococcosis have existed for several millennia, a century has passed since the discovery of this encapsulated yeast and its devastating disease. With the advent of the AIDS pandemic, cryptococcal meningitis has emerged as a leading cause of infectious morbidity and mortality and a frequently life-threatening opportunistic mycosis among patients with AIDS. Both basic and clinical research have accelerated in the 1990s, and this review attempts to highlight some of these advances. The discussion covers recent findings, current concepts, controversies, and unresolved issues related to the ecology and genetics of C. neoformans; the surface structure of the yeast; and the mechanisms of host defense. Regarding cell-mediated immunity, CD4+ T cells are crucial for successful resistance, but CD8+ T cells may also participate significantly in the cytokine-mediated activation of anticryptococcal effector cells. In addition to cell-mediated immunity, monoclonal antibodies to the major capsular polysaccharide, the glucuronoxylomannan, offer some protection in murine models of cryptococcosis. Clinical concepts are presented that relate to the distinctive features of cryptococcosis in patients with AIDS and the diagnosis, treatment, and prevention of cryptococcosis in AIDS patients.

Olfactory pathways in three patients with cryptococcal meningitis and acquired immune deficiency syndrome

The olfactory mucosa, bulbs and tracts were examined for the presence of Cryptococcus neoformans in 3 patients with the acquired immune deficiency syndrome (AIDS) and cryptococcal meningitis. Two of them had antibodies against HIV-1 and one had positive serology for HIV-2. Cryptococci were seen in the subarachnoid space around olfactory tracts and bulbs and in the submucosal olfactory nerve fascicles. In one case, olfactory nerve fascicles from the lamina propria were also affected. Olfactory epithelium and respiratory mucosa were not involved. We suggest that Cryptococcus reached the olfactory nerve fascicles through the olfactory pathways for cerebrospinal fluid drainage which might serve as a source of latent cryptococcal infection.

Utility of bronchoscopic sampling techniques for cryptococcal disease in AIDS

Although cryptococcal pneumonia is a well recognized complication of the acquired immunodeficiency syndrome, optimal diagnostic approaches remain to be defined. During a 32-month period (October 1984 to June 1987), 11 patients were diagnosed with CP at our institution. The diagnosis was established in all 11 patients from specimens obtained via fiberoptic bronchoscopy (ten) and/or double-lumen catheter lavage (one). Direct stains of sedimented bronchoalveolar lavage were positive for organisms characteristic of Cryptococcus neoformans in nine of 11 patients. Transbronchial biopsies were positive (special histologic stains) in six of eight patients; bronchial washings were positive (direct smear) in seven of ten patients, the bronchial brushings were positive on stain in six of nine patients, and in one patient, a Wang transbronchial needle aspirate was positive on stain. Fungal cultures were positive on the BAL in seven of 11 patients, and on the bronchial washings in four of ten patients; the TBBx culture samples were all negative (zero of three). The serum cryptococcal antigen titer was elevated (median = 1:1024) in all eight patients in which it was assayed. Our data suggest that BAL and bronchial washings have a combined sensitivity on smear equal to that of TBBx and superior to that of TBBx fungal culture. The TBBx does not appear to be necessary in this setting. In addition, an elevated serum cryptococcal antigen titer appears to be an important adjunct in the evaluation of pulmonary infiltrates in AIDS.

Pulmonary cryptococcosis in AIDS

Cryptococcus neoformans is emerging as an important etiologic agent of disseminated infection in patients with the acquired immunodeficiency syndrome (AIDS). Little attention has been placed on the pulmonary expression of this systemic infection. We report five patients with AIDS and cryptococcosis with primary pulmonary involvement. Patients usually presented with fever, cough, dyspnea, and pleuritic chest pain. Chest x-ray findings varied from localized and diffuse infiltration to lymphadenopathy and pleural effusions. All patients developed disseminated disease despite antifungal therapy. Pulmonary cryptococcosis is a frequent presentation of this infection in patients with AIDS.

Colonization and pathogenesis of Cryptococcus neoformans in gnotobiotic mice

Congenitally immunodeficient nude (nu/nu) mice and their immunocompetent littermates (nu/+) were used to determine whether the absence of thymus-matured T cells would alter the capacity of Cryptococcus neoformans to colonize their mucosal surfaces or enhance their susceptibility to systemic cryptococcosis, or both, following oral challenge. We present data demonstrating that an encapsulated strain of C. neoformans serotype A colonized the alimentary tracts of germfree, conventional, and antibiotic-treated conventional nu/nu mice. Scanning electron microscopy showed that C. neoformans adhered to the epithelial surfaces of the oral cavities, esophagi, and gastrointestinal tracts of monoassociated nu/nu and nu/+ mice, and culture data showed that there were more viable C. neoformans cells in the alimentary tracts of nu/nu mice than of nu/+ mice. Tetracycline-treated conventional nu/nu, but not nu/+, mice were also colonized with C. neoformans following intragastric challenge. C. neoformans-monoassociated and tetracycline-treated conventional nu/nu mice succumbed to disseminated cryptococcosis with cerebral involvement 3 to 4 weeks after oral challenge, whereas no mortality was observed for similarily challenged nu/+ mice. These results demonstrate that an encapsulated strain of C. neoformans can colonize mucosal surfaces and cause systemic cryptococcosis in immunodeficient nu/nu mice, suggesting that the alimentary tract can be a portal of entry for C. neoformans in an immunodeficient host. These data also indicate that functional T cells play an important role in resistance to systemic cryptococcosis of endogenous origin.

Bronchoscopic and radiologic features of Kaposi's sarcoma involving the respiratory system

In a group of 61 patients admitted to New England Deaconess Hospital, Boston, with a diagnosis of acquired immune deficiency syndrome (AIDS), 25 were found to have Kaposi's sarcoma involving the skin and mucous membranes. Of these 25 patients, eight had lesions involving the respiratory system. Radiographically, patients with Kaposi's sarcoma had hilar and mediastinal adenopathy with perihilar parenchymal infiltration which progressed to diffuse bilateral infiltrates over a period of months. This pattern and the tempo of its evolution were distinctly different from the diffuse infiltrates seen in patients with Pneumocystis carinii pneumonia. Bronchoscopy was performed in seven of the eight patients, revealing characteristic lesions of Kaposi's sarcoma in the airways. We propose that parenchymal pulmonary Kaposi's sarcoma can be strongly suspected in a patient with AIDS who has the following features: a characteristic radiologic pattern; endobronchial Kaposi's sarcoma at bronchoscopy; and no evidence of opportunistic infection. In this subset of patients, further diagnostic intervention such as open lung biopsy, a procedure with potential morbidity in these ill individuals, may be unnecessary.

Pulmonary cryptococcosis

Observation of an unusual pulmonary distribution of cryptococci in a patient at autopsy prompted a review of 36 patients with pulmonary cryptococcosis listed in the autopsy files of The Johns Hopkins Hospital. The patients ranged in age from 2 to 89 years (mean, 49 years), 19 were female, and 18 were black. All but three patients had underlying debilitating diseases, and 23 patients had received steroids and/or chemotherapy. In 25 patients (69 per cent) cryptococcosis was a major factor contributing to death, through pulmonary disease in ten, systemic involvement in seven, and central nervous system disease in eight. In 15 patients (42 per cent) cryptococcosis was diagnosed clinically. Four basic morphologic patterns were observed: 1) Seven patients (19 per cent) had one or more peripheral pulmonary granulomas. In three of these patients the granulomas were apparently quiescent, and no other lesions were found. 2) Nineteen patients (53 per cent) had what has been called granulomatous pneumonia, with intra-alveolar proliferating organisms and varying degrees of inflammatory response, which, when present, ranged from acute inflammation to diffuse intra-alveolar granulomas with giant cells. 3) In seven patients (19 per cent) organisms were present diffusely within alveolar capillaries and interstitial tissues, and reactions ranged from little or no inflammation with numerous organisms to few organisms with miliary granulomas. 4) In three patients (8 per cent) both intra-alveolar and intravascular organisms were present in massive numbers, and the primary route of infection was uncertain. Fatalities from pulmonary and generalized infection occurred in patients in each histologic group. The results show marked variability both in pathologic reaction to cryptococci and in the clinical appreciation and significance of pulmonary cryptococcosis.

Survey of Cryptococcus neoformans in the respiratory tract of patients with bronchopulmonary disorders and in the air

Cryptococcus neoformans was cultured from 9 (1%) of 835 clinical specimens examined from the respiratory tract of patients. These isolations came from 3 (0.4%) of the760 patients; 8 isolates were from sputum and one from urine. The fungus was not demonstrable in the air at a selected site during a 2-year study although other species of Cryptococcus, namely, C. albidus, C. ater, C. flavus, C. laurentii, C. magnus, C. terreus and C. uniguttulatus were isolated. The three C. neoformans positive patients were males, with pulmonary tuberculosis as the primary disease and history of repeated exposure to pigeon excreta in two. None of these patients manifested any overt signs and symptoms specificially attributable to cryptococcosis, nor did they receive any antifungal therapy. Repeated isolations of C. neoformans from sputum, a positive urine culture and demonstration of cryptococcal antibodies in a serum specimen, followed by negative cultures and serology, suggested that patient 1 had spontaneously recovered from an episode of benign, minimal pulmonary cryptococcosis. Patients 2 and 3 probably carried the fungus as a transient resident of the respiratory tract. The results suggest that C. neoformans is of uncommon occurrence in the respiratory tract of patients with bronchopulmonary disorders and that the isolation of the fungus from this site may not necessarily imply an etiologic relationship.

Occurrence and significance of Cryptococcus neoformans in the oropharynx and on the skin of a healthy human population

Cryptococcus neoformans was cultured on one occasion from the oropharyngeal washings in 1 of 820 and from the interdigital areas of the feet in 6 of 723 healthy persons. Among the positive persons were two school children, two laboratory workers, one gardener, one plumber, and one printing press worker. Repeat cultures were negative in all seven positive persons; serological tests for cryptococcal antigen/antibody were negative in three. The results demonstrate that C. neoformans may occur as a transient inhabitant of the oropharynx or skin of healthy people.

Cryptococcosis, with emphasis on the significance of isolation of Cryptococcus neoformans from the respiratory tract

Cryptococcus neoformans was isolated from 65 patients: 11 had meningitis, 11 had disseminated cryptococcosis without meningitis, and 43 had C neoformans isolated from the respiratory tract. Predisposing conditions and the diagnostic value of cultures from various sites and of the latex agglutination test on cerebrospinal fluid and serum are analyzed for patients with extrapulmonary disease. Nine patients had pleural effusions; the effusion was cultured in six and yielded C neoformans in four. None of 11 deaths among 43 patients with respiratory tract isolates could be attributed to cryptococosis. The 32 survivors were nor treated with antifungal agents. Twenty-six of 43 patients with respiratory isolates had various bronchopulmonary disorders, with chronic obstructive pulmonary diseases and asthma the most common (28 percent). Seven of 28 patients (25 percent) with roentgenographically detected lung lesions had carcinoma of the lung. Roentgenographic evidence of a lung lesion and C neoformans grown from the respiratory tract warrant a further search for carcinoma of the lung.

Cryptococcosis in a cancer hospital: clinical and pathological correlates in forty-six patients

The clinical and pathological findings in 46 patients with cryptococcosis at Memorial Sloan-Kettering Cancer Center from 1956 to 1972 are reported. The striking predilection for cryptococcal infection in patients with leukemias and lymphomas is again confirmed. Of 41 patients with neoplastic disease, those with chronic lymphatic leukemia (CLL), Hodgkin's Disease, chronic myelogenous leukemia (CML), myeloma and lymphosarcoma had the highest incidence of cryptococcosis. In all cases, neoplastic disease was widespread when infection occurred. All of these patients had leukopenia and absolute lymphopenia at the time of infection. Thirty-nine were on steroids. Thirty-one patients with neoplastic disease had disseminated infection. Review of pathology revealed a spectrum of inflammatory lesions. Histiocytic-lymphocytic infiltrates occurred in the central nervous system in 10 patients. In six cases, reaction was granulomatous. There were single instances of suppurative and fibrotic reactions. Mortality from infection was high in patients with neoplastic disease. Twenty-four of 28 deaths occurred within 60 days as a result of infection. Within one year, 10 more patients died, nine of cryptococcosis. Only three survived more than one year, and all patients died within 600 days. Twenty-nine patients with neoplastic disease received amphotericin B. Only nine survived more than 60 days.

Occurrence and significance of Cryptococcus neoformans in the respiratory tract of patients with bronchopulmonary disorders

Cryptococcus neoformans was cultured from 13 (3%) of 469 clinical specimens examined from the respiratory tract of patients with bronchopulmonary diseases. These isolations came from 5 (2%) of 207 patients; 11 isolates were from sputum and 1 each were from bronchoscopic aspirate and empyema pus. The fungus was not cultured from the oropharyngeal washings of 101 apparently healthy volunteers. Of the 5 patients, 3 had pulmonary tuberculosis, including one with pyopneumothorax and 2 with allergic bronchopulmonary aspergillosis as the underlying disease. In the tuberculosis patient with pyopneumothorax and C. neoformans in empyema pus, the fungus was presumably a tissue invader, whereas its role could not be unequivocally ascertained in the remaining 4 patients from whom it was isolated from sputum or bronchial aspirate on at least two consecutive occasions. The question of C. neoformans being a transient resident, commensal, or incitant of benign minimal lesions in the tracheobronchial tree is discussed. A comprehensive laboratory and clinical follow-up is warranted in patients from whose sputum or bronchial aspirate C. neoformans may be cultured even though definitive signs of cryptococcosis may be lacking.

Vaccine and Mycostatin in treatment of cryptococcosis of the respiratory tract

Three cases of respiratory crytococcosis are described, one diagnosed only after thoracotomy and two after cytology. All were confirmed by cultures, biological and biochemical tests. The patients are alive and well 14 years, 5 years, and 5 years after treatment with crytococcal vaccines and mycostatin. Vaccines proved very effective when given intradermally in small doses and no dangerous reactions were encountered. Cytology of the sputum appears to be a very useful tool in diagnosis of fungal infections of the respiratory tract, especially when supravital staining is used. Difficulties in diagnosis, treatment, and significance of positive sputum findings are discussed.

The incidence and management of pulmonary mycosis in renal allograft patients

A retrospective analysis of 193 renal transplant recipients yielded 15 patients who developed pulmonary mycosis posttransplantation and one case in which mycotic lung infection existed at the time of transplant surgery. Agent responsible for infection included Nocardia asteroides in 8 cases, Asperigillus flavus in 5 cases, Cryptococcus neoformans in 4 patients and Candida albicans in 2 cases. Two cases had mixed mycotic infections. Ten patients died, of which 7 had diagnosis established antemortem. Two cases had diagnosis established by thoracotomy and 1 case by transtracheal aspiration. Problems in establishing accurate diagnosis are discussed with emphasis placed on the need for more frequent use of transtracheal aspiration and thoracotomy for precise diagnosis.