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

Cryptococcus neoformans Genotypic Diversity and Disease Outcome among HIV Patients in Africa

Cryptococcal meningoencephalitis, a disease with poor patient outcomes, remains the most prevalent invasive fungal infection worldwide, accounting for approximately 180,000 deaths each year. In several areas of sub-Saharan Africa with the highest HIV prevalence, cryptococcal meningitis is the leading cause of community-acquired meningitis, with a high mortality among HIV-infected individuals. Recent studies show that patient disease outcomes are impacted by the genetics of the infecting isolate. Yet, there is still limited knowledge of how these genotypic variations contribute to clinical disease outcome. Further, it is unclear how the genetic heterogeneity of C. neoformans and the extensive phenotypic variation observed between and within isolates affects infection and disease. In this review, we discuss current knowledge of how various genotypes impact disease progression and patient outcome in HIV-positive populations in sub-Saharan African, a setting with a high burden of cryptococcosis.

First case report of fulminant septic shock from meningococcemia associated with Cryptococcus neoformans coinfection in an immunocompetent patient

The meningococcal disease manifestation associated with the presence of Cryptococcus neoformans is rare. There are no reports in the literature about these simultaneous infections in immunocompetent patients. The aim of the present study is to describe the first case of fulminant septic shock by Neisseira meningitidis associated with Cryptococcus neoformans coinfection in an immunocompetent patient. We describe a case of an immunocompetent 74-year-old Caucasian woman who presented with fulminant acute meningococcemia associated with cryptococcal meningitis, which progressed to worsening general condition and died of septic shock and multiple organ dysfunctions in less than 48 hours. This case report demonstrates the possibility of coinfections related to Neisseria meningitidis and Cryptococcus neoformans, even in immunocompetent patients, which represent a diagnostic challenge for clinicians, thus encouraging further studies for a better understanding.

•

Meningococcal infections disseminate early, leading to fulminant disease.

•

Cryptococcus neoformans meningitis is uncommon in immunocompetent patients.

•

The association between meningococcal disease and Cryptococcus neoformans infection is very rare and requires a fast diagnosis and management.

•

The real cause of coinfection between Cryptococcus neoformans and Meningococcal disease in immunocompetent patients remains uncertain.

Isolated Pulmonary Cryptococcosis in an Immunocompetent Patient Presenting with Right Shoulder Pain: A Case Report and Review of the Literature

Cryptococcosis is an important systemic fungal infection occurring predominantly in immunocompromised patients. We report a case of isolated pulmonary cryptococcosis in an ambulant middle-age lady who presented to the emergency department with right shoulder pain. The clue to lung pathology was right apical haziness best seen in the apical lordotic radiograph. The diagnosis was established by transbronchial lung biopsy. She did not have underlying immunosuppression or extrapulmonary disease. She was closely observed without anti-fungal therapy, and showed radiographic improvement during the five-month period of follow up.

Pulmonary Cryptococcosis Presenting With Lung Mass: Report of 7 Cases and Review of Literature

Pulmonary cryptococcosis is commonly found in immunocompromised patients. This microorganism rarely infects immunocompetent individuals, and when it does, it causes mild symptoms. The radiological findings of this disease may involve an intrapulmonary mass that mimics lung tumor. The objective of this study was to review the clinicopathological information, radiological findings, and treatment of patients who presented with intrapulmonary mass due to cryptococcosis. This study collected data from 7 patients who were treated at Songklanagarind Hospital, Songkhla, Thailand, between 2009 and 2014. Their clinical data, radiological findings, pathological results, and treatment protocols were reviewed. The patients were 2 women and 5 men, ranging in age from 37 to 79 years old. One case was an immunocompromised host. Four cases experienced the chest symptoms of dyspnea, hemoptysis, and chronic cough. The most common location of mass was the left lower lobe (71%). Four cases had a history of bird contact. Lung lobectomy was performed in 3 cases (42%), and all of the patients were treated with oral fluconazole. An intrapulmonary mass caused by this microorganism is mainly found in immunocompetent patients. Treatment with the antifungal drug fluconazole is very effective.

Disseminated cryptococcosis in an immunocompetent patient

Cryptococcosis is a fungal infection which is commonly associated with immune-compromised state. Disseminated infection in immunocompetent individuals is extremely rare. We present a case of a 56-year-old African American patient who presented with unilateral knee pain and swelling and was subsequently diagnosed with cryptococcal bone mass with dissemination of infection.

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.

Pulmonary Fungal Diseases in Immunocompetent Hosts: A Single-Center Retrospective Analysis of 35 Subjects

BACKGROUND

Pulmonary fungal disease is an emerging issue in immunocompetent patients, for whom the characteristics are only partially understood.

METHODS

We conducted a single-center retrospective study of histologically verified pulmonary fungal disease in Eastern China from 2006 to 2014 to understand the demographics, clinical manifestations, therapeutic approaches, and factors associated with prognosis in this population. All cases were diagnosed according to the 2008 European Organization for the Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and the National Institute of Allergy and Infection Diseases Mycoses Study Group definition criteria.

RESULTS

A total of 112 cases of pulmonary fungal diseases were enrolled (35 proven, 16 probable, 61 possible), and we analyzed the 35 patients with histologically proven pulmonary fungal diseases in this study. The main fungal species identified were Aspergillus (51.4 %), Cryptococcus (22.9 %), and Mucor (2.4 %). Treatment consisted of antifungal therapeutic agents (54.3 %), surgery and postsurgical agents (25.7 %), or surgery alone (14.3 %). The overall crude mortality rate was 14.3 %, and the mortality due to pulmonary fungal infections was 2.9 %. Significant predictors of mortality by univariate analysis were hypoalbuminemia (P = 0.005), cancer (P = 0.008), and positive culture (P = 0.044). Additionally, hypoalbuminemia was the only risk factor for mortality by multivariate analysis (RR = 7.56, 95 % CI 1.38-41.46).

CONCLUSION

Pulmonary fungal disease in immunocompetent patients, with Aspergillus as the most common identified species, had a prognosis that was influenced by the level of serum albumin.

Disseminated cryptococcosis with adrenal and lung involvement in an immunocompetent patient

Disseminated cryptococcosis usually occurs in immunocompromised patients. Occasionally, it affects immunocompetent persons and mimics tuberculosis in clinical presentation and radiological findings. Usually, it affects lungs and central nervous system. Rarely, it may affect adrenal glands. We present a case of 65-year-old gentleman with prolonged pyrexia. Computed Tomography (CT) scan of chest and abdomen showed miliary pattern in the chest with bilateral adrenal masses. On the basis of clinical and radiological findings, the case was initially diagnosed as disseminated tuberculosis and anti tubercular treatment was started. Subsequently, on histopathological examination, the diagnosis was confirmed as disseminated cryptococcosis. Even in a country with high prevalence of tuberculosis, other causes of miliary mottling should be considered and histopathological examination should be sought.

Pulmonary cryptococcosis: comparison of CT findings in immunocompetent and immunocompromised patients

BACKGROUND

Computed tomography (CT) findings in patients with pulmonary cryptococcosis have been reported, however, many reports were limited by the small number of patients, and not taken into account the distinction between immunocompetent and immunocompromised patients.

PURPOSE

To retrospectively evaluate thoracic CT findings in patients with pulmonary cryptococcosis whose immune status ranged from normal to severely compromised, and determine characteristic imaging features of pulmonary cryptococcosis between patients with different immune status.

MATERIAL AND METHODS

CT scan findings of 29 immunocompetent and 43 immunocompromised patients with clinically proven pulmonary cryptococcosis were reviewed retrospectively. Different patterns of CT scan abnormalities between immunocompromised and immunocompetent patients, AIDS and non-AIDS immunocompromised patients were compared by Fisher's exact test.

RESULTS

Pulmonary nodules/masses, either solitary or multiple, were the most common CT finding, present in 65 (90.3%) of the 72 patients; associated findings included CT halo sign (n = 24), cavitation (n = 23), and air bronchogram (n = 17). Areas of consolidation (n = 14), areas of GGO (n = 13), linear opacities (n = 11), lymphadenopathy (n = 5), and pleural effusion (n = 8) were uncommon. The parenchymal abnormalities were peripherally located in 47 (65.2%) of the cases. Cavitations within nodules/masses were more frequently present in immunocompromised patients than in immunocompetent patients (P = 0.009), and in AIDS patients than in non-AIDS immunocompromised patients (P = 0.002). Air bronchograms within nodules/masses were more frequent present in immunocompetent patients than in immunocompromised patients (P = 0.005). Nodules/masses with halo sign were less frequent in AIDS patients than those in non-AIDS immunocompromised patients (P = 0.027).

CONCLUSION

Pulmonary cryptococcosis should be considered in the differential diagnosis of solitary or multiple pulmonary nodules. Cavitations within nodules/masses were more commonly seen in immunocompromised patients, especially AIDS patients, while air bronchograms were more commonly seen in immunocompetent patients.

Pulmonary cryptococcosis that mimicked rheumatoid nodule in rheumatoid arthritis lesion

Recently, the incidence of pulmonary cryptococcosis is gradually increasing in rheumatoid arthritis (RA) patients. Pulmonary rheumatoid nodules (PRN) are rare manifestations of RA. Eighteen months ago, a 65-year old woman was admitted to hospital due to multiple nodules (2.5×2.1×2 cm) with cavitations in the right lower lobe. She was diagnosed with RA three year ago. She had been taking methotrexate, leflunomide, and triamcinolone. A video-assisted thoracoscopic surgery biopsy was performed and PRN was diagnosed. However, a newly growing huge opacity with cavitation was detected in the same site. Pulmonary cryptococcal infection was diagnosed through a transthoracic computed tomograpy guided needle biopsy. Cryptococcus antigen was detected in serum but not in cerebrospinal fluid. The patient was treated with oral fluconazole which resulted clinical improvement and regression of the nodule on a series of radiography. Herein, we report the case of pulmonary cryptococcosis occurring in the same location as that of the PRN.

A rare case of Cryptococcus luteolus-related tenosynovitis

A 68-year-old male with type II diabetes mellitus presented with a nodule over the metacarpophalangeal joint of his right second finger after being spurred on the hand by a domestic turkey 2 weeks prior to onset of clinical symptoms. He was diagnosed with cryptococcal tenosynovitis caused by Cryptococcus luteolus identified by DNA sequencing. Complete clinical resolution was achieved with synovectomy and debridement followed by 1 year of fluconazole 800 mg daily.

Case of pulmonary cryptococcosis mimicking hematogeneous metastases in an immunocompetent patient: value of absent 18F-fluorodeoxyglucose uptake on positron emission tomography/CT scan

The radiologic appearance of multiple discrete pulmonary nodules in immunocompetent patients, with cryptococcal infection, has been rarely described. We describe a case of pulmonary cryptococcosis, presenting with bilaterally and randomly distributed nodules on a computed tomography, mimicking hematogeneous metastases. Positron emission tomography does not demonstrate 18F-fluorodeoxyglucose (FDG) uptake, suggesting a low probability for malignancy, which is a crucial piece of information for clinicians when making a management decision. We find the absence of FDG uptake correlates with the pathologic finding of an infectious nodule, composed of fibrosis and necrosis.

Identification of fungal diseases at necropsy

The purpose of the Death Verification Service is to elucidate the causes of deaths that occur without medical assistance and of ill-defined deaths. In recent decades, the epidemiological reality of fungal infections has changed due to the rise in opportunistic infections chiefly in immunocompromised patients. A study of fungal diseases in autopsies performed in the Death Verification Service of the Medicine School in São José do Rio Preto between January 2000 and December 2009 was made. Sixty-seven cases of fungal disease, most involving men (70%), were found in 4824 autopsies. Cryptococcosis was the most prevalent (45%), followed by paracoccidioidomycosis, candidiasis, histoplasmosis, aspergillosis and mucormycosis. Associations between AIDS (n=14) and fungal diseases were identified for cryptococcosis (36%), candidiasis (28.5%) and histoplasmosis (28.5%). Pneumonia, AIDS and fungal diseases were evident in 26% of the cases, with the most prevalent etiologies being Cryptococcus neoformans (55.5%) and Histoplasma capsulatum (22%). Pneumonia alone occurred in 43% of cases, with cryptococcosis (53%) and paracoccidioidomycosis (33%) being the main infectious agents. Diabetes mellitus was associated with candidiasis in two cases and aspergillosis in one. One case of renal transplantation linked to paracoccidioidomycosis and one case of bone marrow aplasia with mucormycosis were reported. Despite the reduction in the number of autopsies over recent decades, these findings suggest that this procedure is useful to provide additional data on the etiology, underlying disease and specific risk factors, essential for quality control and to improve treatment protocols.

Cryptococcus pneumonia presenting in an immunocompetent host with pulmonary asbestosis: a case report

INTRODUCTION

Cryptococcal infections pose a diagnostic challenge in an immunocompetent host. Asbestos exposure has been associated with pulmonary aspergillosis. This case highlights an interesting presentation of cryptococcal lung inflammation with underlying asbestosis.

CASE PRESENTATION

A 63-year-old Mediterranean Caucasian woman presented with progressive dry cough of nine months duration. A computed tomography (CT) scan of her chest revealed multiple foci in the right infra-hilar region, which were seen as hot lung masses on a positron emission tomography (PET) scan. These multiple foci appeared metastatic in nature throughout both lung fields with early mediastinal invasion. A computed tomography (CT)-guided core biopsy was obtained from a dominant right lower lobe lung mass. Histology showed chronic granulomatous inflammation with numerous budding yeast forms that were GMS-, PAS-, and mucin-positive, consistent with cryptococcosis together with asbestos bodies (ferruginous). She was managed with fluconazole (400mg (6mg/kg) per day orally) daily. At her six-month follow up, she had marked improvement in her general condition along with a diminution of the lower lobe lung mass.

CONCLUSION

We report a clinical and radiological improvement in a patient treated for cryptococcal pneumonia. Asbestos exposure was likely to have been an important pathophysiological precursor to infection by environmental fungi.

Disseminated cryptococcosis in an immunocompetent patient: a case report

Cryptococcus neoformans is ubiquitous encapsulated yeast found throughout the world. It predominantly causes significant infections in immunocompromised individuals, of which 80-90% occur in people with human immunodeficiency virus (HIV) infection. Disseminated cryptococcal infection is uncommon and almost always occurs in HIV-infected patients. Disseminated disease, especially noncutaneous cryptococcal abscess in immunocompetent hosts, is exceedingly rare. We report a case of disseminated cryptococcosis with soft tissue, pulmonary, and cerebral involvement in an otherwise healthy immunocompetent patient initially diagnosed by fine needle aspiration cytology (FNAC).

Treatment of asymptomatic pulmonary cryptococcosis in immunocompetent hosts with oral fluconazole

BACKGROUND

Pulmonary cryptococcosis is occasionally detected on routine imaging studies in healthy hosts with no or mild symptoms. Isolated pulmonary cryptococcosis may be observed without specific therapy in asymptomatic immunocompetent hosts. However, considering that dissemination from a pulmonary infection can occur in patients with no immunologic defects, treatment of asymptomatic pulmonary cryptococcosis in immunocompetent hosts remains controversial. The aim of this study was to determine the role of fluconazole therapy in the management of isolated pulmonary cryptococcosis in asymptomatic healthy hosts.

METHODS

We retrospectively analyzed the medical records and radiographic findings of 10 healthy subjects with isolated pulmonary cryptococcosis diagnosed incidentally and treated with oral fluconazole.

RESULTS

All patients had no respiratory or constitutional symptoms. The most common radiological findings were pulmonary nodules, and the number of nodules in each patient was from 1 to 9. After histological confirmation, all patients were treated with oral fluconazole at a dosage of 400 mg per day for a median period of 6.4 months. No patient developed an adverse reaction to fluconazole. The mean interval between the initiation of antifungal therapy and final radiological response was 8.3 months. Seven of the 10 patients showed complete resolution, and the other 3 patients were assessed as having partial resolution. During the average follow-up period of 11.9 months, all patients showed a favourable outcome with no relapse. The overall cure rate was 70%.

CONCLUSION

These results suggest that fluconazole may be an attractive therapeutic option for asymptomatic pulmonary cryptococcosis in immunocompetent hosts.

Clinical practice guidelines for the management of cryptococcal disease: 2010 update by the infectious diseases society of america

Cryptococcosis is a global invasive mycosis associated with significant morbidity and mortality. These guidelines for its management have been built on the previous Infectious Diseases Society of America guidelines from 2000 and include new sections. There is a discussion of the management of cryptococcal meningoencephalitis in 3 risk groups: (1) human immunodeficiency virus (HIV)-infected individuals, (2) organ transplant recipients, and (3) non-HIV-infected and nontransplant hosts. There are specific recommendations for other unique risk populations, such as children, pregnant women, persons in resource-limited environments, and those with Cryptococcus gattii infection. Recommendations for management also include other sites of infection, including strategies for pulmonary cryptococcosis. Emphasis has been placed on potential complications in management of cryptococcal infection, including increased intracranial pressure, immune reconstitution inflammatory syndrome (IRIS), drug resistance, and cryptococcomas. Three key management principles have been articulated: (1) induction therapy for meningoencephalitis using fungicidal regimens, such as a polyene and flucytosine, followed by suppressive regimens using fluconazole; (2) importance of early recognition and treatment of increased intracranial pressure and/or IRIS; and (3) the use of lipid formulations of amphotericin B regimens in patients with renal impairment. Cryptococcosis remains a challenging management issue, with little new drug development or recent definitive studies. However, if the diagnosis is made early, if clinicians adhere to the basic principles of these guidelines, and if the underlying disease is controlled, then cryptococcosis can be managed successfully in the vast majority of patients.

Cryptococcosis: an emerging respiratory mycosis

Cryptococcosis occurs in immunocompromised and, in special cases, immunocompetent individuals. There have been a number of important advances in the field, but, despite current treatment, patients continue to die of the infection. This article reviews cryptococcosis epidemiology, clinical features, and management. Current knowledge is incomplete, however, so this article also discusses some of the gaps in the present understanding of cryptococcosis. The hope is that current research striving to understand the mechanisms of host evasion of Cryptococcus will result in improved treatment regimens that decrease both the mortality and morbidity of cryptococcosis.

Clinical and radiographic presentations of pulmonary cryptococcosis in immunocompetent patients

Pulmonary cryptococcosis is often noted in immunocompromized patients, especially in HIV-seropositive patients and post-transplant patients. Only a few case reports and small-scale studies on pulmonary cryptococcosis in immunocompetent patients have been published in the English literature. However, there are several areas of uncertainty in this group of patients including image presentations and management strategy. This retrospective study including 17 patients is designed to share our 7 y of experience in clarifying the characteristics of pulmonary cryptococcosis in immunocompetent patients, including initial symptoms, diagnostic criteria, pulmonary imaging, treatment and outcome in a tertiary teaching hospital in Taiwan.

Laccase activity in Cryptococcus gattii strains isolated from goats

Cryptococcosis is a life-threatening infection in humans and animals caused by encapsulated yeasts of the genus Cryptococcus. Cryptococcus neoformans and Cryptococcus gattii are the main agents of this mycosis. Until 2002 C. gattii was classified as a variety of C. neoformans but now is accepted as an independent species. The laccase (phenoloxydase) enzyme produced by these yeasts is considered one of the main pathogenic factors for its ability to induce melanin from dihydroxyphenolic compounds. The vast majority of the studies in laccase and melanin synthesis have been developed using isolates of C. neoformans. The main objective of this study was to evaluate laccase activity in strains of C. gattii, serotype B isolated from immunocompetent goats that died of lung and disseminated cryptococcosis, in several outbreaks occurring in Spain. The laccase activities of these isolates were compared with those of other strains of C. gattii and C. neoformans. After fungal cell rupture, the supernatant of each isolate was analyzed for its laccase activity using as substrate an L-dopa 20 mM solution. The degree of enzymatic activity was assessed according to its absorbance at 450 nm and scored using Enzymatic Units (EU). The maximum values were observed in three strains of C. gattii from goats (EU > 12). The smallest values were observed in one environmental isolate of C. gattii serotype C (EU = 0.7). The highest recorded value for C. neoformans was 6.3 EU in a serotype A isolate from one human case of meningitis. C. gattii serotype B obtained from goats showed different degrees of laccase activity, being the highest in those isolated from severe outbreaks of cryptococcosis. This enzyme appears to represent a major, though nonexclusive, pathogenic factor for Cryptococcus gattii.

Fungal Infections

Older adults are at increased risk of developing opportunistic fungal infections because organ transplantation, intensive cancer chemotherapy regimens, and anti-tumor necrosis factor agents are now used more commonly, and because admission to an intensive care unit, which carries many risk factors for fungal infection, has become commonplace in this group.

Candida species are the most common cause of opportunistic fungal infections, and bloodstream infections are usually treated with fluconazole or an echinocandin antifungal agent.

Invasive mold infections are mostly caused by Aspergillus species; in older adults, they cause primarily pulmonary and sinus infections, and they are associated with a high mortality rate.

The endemic fungi, Histoplasma capsulatum, Coccidioides species, and Blastomyces dermatitidis, cause infection when the mold form is dispersed and inhaled from the environment in those specific areas of the country in which these organisms flourish.

Amphotericin B is used for initial treatment of severe histoplasmosis, coccidioi­domycosis, and blastomycosis; itraconazole is the therapy of choice for most mild to moderate infections due to these endemic mycoses.

Cryptococcus meningitis and skin lesions in an HIV negative child

Disseminated cryptococcosis is an uncommon occurrence in immunocompetent populations and occurs mainly in immunocompromised patients. The first case of cryptococcus meningitis and skin lesions in a 4-year-old confirmed HIV negative boy who presented with fever, meningism and skin lesions is reported. On examination the child was confused, uncooperative, and had neck stiffness and raised skin lesions. A septic screen, including skin scraping, was performed; the child was treated with penicillin and ceftriaxone for suspected meningococcal meningitis. The cerebrospinal fluid (CSF) had normal protein, glucose and chloride levels; yeasts were observed on Gram stain from the CSF and skin scraping. The India ink stain and Cryptococcus neoformans latex agglutination test on the CSF were both positive. Bacterial culture of the skin biopsy, CSF and blood culture specimens was negative. The child was treated with amphotericin B based on preliminary results, and had a gradual recovery with no neurological sequelae. The child continued oral fluconazole.

Pulmonary cryptococcosis: Clinical, radiographical and serological markers of dissemination

BACKGROUND AND OBJECTIVE

This study aimed to identify markers of disseminated infection in patients presenting with pulmonary cryptococcosis.

METHODS

Patients diagnosed with pulmonary cryptococcosis at a tertiary hospital between April 1998 and April 2005 were included and their clinical, radiological and pathological data analysed retrospectively.

RESULTS

Thirty-one patients (14 male) were recruited into the study. Disseminated infection was seen in nine patients (29%), with the isolation of Cryptococcus neoformans from the blood of five patients and the cerebrospinal fluid of seven (three patients had both positive blood and cerebrospinal fluid findings). Patients with disseminated infection had a significantly higher incidence of impaired cellular immunity (immunosuppressant use, AIDS and haematological malignancy) (P = 0.015), fever (P < 0.001), interstitial abnormalities on CXR (P < 0.001), pleural effusion (P = 0.017) and death (P = 0.04) when compared with patients with localized infection. Serum cryptococcal antigen (sCRAG) was positive in 17 of the 19 patients tested at the time of diagnosis. Significantly higher sCRAG titres were noted in patients who had fever (P = 0.001), interstitial abnormalities on CXR (P = 0.004), pleural effusion (P = 0.018), disseminated disease (P = 0.003) and in those who died (P = 0.05).

CONCLUSIONS

In pulmonary cryptococcosis patients, the presence of fever, interstitial abnormalities on CXR or pleural effusion should lead clinicians to suspect disseminated infection. High titres of sCRAG may indicate more extensive extra-pulmonary involvement and a worse prognosis.

Cryptococcosis-a review of 13 autopsy cases from a 54-year period in a large hospital

From 1952 to 2005, 13 cases of cryptococcosis confirmed by postmortem examination were diagnosed in autopsy material from the University Hospital in Hradec Králové, the Czech Republic. Histologically, Cryptococcus was found in multiple organs (brain and spinal cord, lungs, lymph nodes, spleen, bone marrow, liver, kidneys and adrenal glands). The lungs and CNS were the organs most often involved. Only in two cases was the diagnosis of cryptococcal infection established during the patient's lifetime, in both presenting clinically as meningitis, with positive result of CSF cultivation. Data and issues of diagnostics and treatment of cryptococcosis are discussed.

[Cryptococosis: clinical epidemiological laboratorial study and fungi varieties in 96 patients]

Ninety-six patients with cryptococcosis confirmed by clinical and laboratorial diagnosis were assessed in a prospective study in a University Hospital from March 1998 to November 2003; of these, 81.3% were HIV seropositive patients. Cryptococcus neoformans was isolated from different samples, of which the cerebrospinal fluid 74 (77%) was the most frequent. C. neoformans var neoformans was isolated in 89 cases, where as C. neoformans var gattii was isolated in 7. Cryptococcal meningoencephalitis was detected in 56.3% cases. It was the most frequent unique clinical manifestation and the fungus was detected in the bloodstream in 13.5% of the patients. Among the risk factors, AIDS (81.3%) was the most frequently associated with mycosis. Direct examination carried out on 121 samples revealed the microorganism in 98.3% of them, while the culture was positive for all samples. Most of the patients (59.4%) were treated with amphotericin B or with triazoles, however 72.9% of them ended in death, in particular those patients with positive tests for the HIV (62.5%). Nowadays, cryptococcosis has been frequently diagnosed in our region and represents one of the opportunistic diseases with the highest morbidity and mortality rates in patients with AIDS.

Criptococose pulmonar isolada em paciente imunocompetente

O presente trabalho relata um caso de criptococose pulmonar isolada em paciente com sintomas respiratórios, sem imunossupressão e sorologia negativa para o vírus da imunodeficiência humana, com massa pulmonar no radiograma de tórax. O diagnóstico foi confirmado pela biópsia transbrônquica e lavado broncoalveolar. A paciente recebeu tratamento ambulatorial com fluconazol, na dose de 300 mg/dia por seis meses, evoluindo com melhora clínica e regressão parcial da imagem radiológica. O presente caso ilustra uma apresentação não freqüente da criptococose pulmonar e faz considerações sobre a abordagem terapêutica com base na literatura.

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.

Pulmonary cryptococcosis: comparison of clinical and radiographic characteristics in immunocompetent and immunocompromised patients

STUDY OBJECTIVES

We compared the clinical characteristics and imaging findings between immunocompetent and immunocompromised patients in whom pulmonary cryptococcosis had been diagnosed to define the role of serum cryptococcal antigen (sCRAG) and radiographs during a follow-up period of up to 1 year.

DESIGN

Retrospective cohort study.

SETTING

University hospital.

PATIENTS

The clinical records, chest radiographs, and CT scan findings of 13 immunocompetent and 16 immunocompromised patients with a diagnosis based on cerebrospinal fluid (CSF) culture, sCRAG titers, and cytologic or histologic confirmation of the presence of pulmonary cryptococcosis were reviewed during the course of the study. Two thoracic radiologists reviewed chest radiographs and CT scans for morphologic characteristics and the distribution of parenchymal abnormalities, and a final reading was reached by consensus. The correlation between serial radiographs and sCRAG titers was examined in 9 immunocompetent and 10 immunocompromised patients.

MEASUREMENTS

Serum or CSF cryptococcal antigen.

RESULTS

The most common clinical symptom was cough, which was present in 24 patients (82.8%). Pulmonary nodules were the most frequent radiologic abnormality. Cavitation within nodules and parenchymal consolidation were significantly less common in immunocompetent patients compared to immunocompromised patients (p = 0.02 and p = 0.05, respectively). Immunocompromised patients tended to have a larger extent of pulmonary involvement than immunocompetent patients, the changes seen on their serial radiographs were more variable, and their corresponding sCRAG titers were higher (> 1:256). In the immunocompetent patients, the radiographic characteristics of lesions usually improved with a corresponding decrease in sCRAG titers over time.

CONCLUSIONS

Our study suggests that pulmonary cryptococcosis usually follows a benign clinical course in immunocompetent patients. Immunocompromised patients often undergo an evolution to cavitary lesions that represent a more aggressive disease nature. Serial radiographic changes and changes in sCRAG titers reliably reflect disease progression and the response to therapy.

Pulmonary Cryptococcosis in Immunocompetent Patients: CT Findings in 12 Patients

OBJECTIVE

The aim of our study was to review the CT findings of pulmonary cryptococcosis in 12 immunocompetent patients.

CONCLUSION

The CT manifestations of pulmonary cryptococcosis consist of pulmonary nodules or masses measuring 5-52 mm in diameter and focal areas of consolidation. The nodules and masses have a predominantly peripheral distribution in 80% of the cases. Cavitation of nodules or consolidation is seen in approximately 40% of the cases. The infection can be due to Cryptococcus neoformans var gattii or var neoformans.

Large cryptococcoma mimicking lung cancer in an HIV-negative, type 2 diabetic patient

Pulmonary cryptococcoma is an unusual disease in immunocompetent patients. The typical radiologic findings are single or multiple small nodules. We describe a case of a large pulmonary cryptococcoma in a 69-year-old patient, who presented with generalized weakness and poor appetite. Computed tomography of the chest showed a large mass that was strongly suggestive of lung cancer. Pulmonary cryptococcal infection was diagnosed by transthoracic needle biopsy. Human immunodeficiency virus testing was negative. The mass resolved with 200 mg daily of oral fluconazole over the course of 6 months.

Cryptococcus infection in tropical Australia

Eighteen cases of disease caused by the saprophytic fungi Cryptococcus neoformans and Cryptococcus bacillisporus are described from the Northern Territory of Australia. The majority of infections were with Cryptococcus bacillisporus and in the rural Aboriginal population, often causing pulmonary mass lesions.

[Disseminated pulmonary infection due to Cryptococcus neoformans in a non immunocompromised patient]

We report a case of a primary pulmonary infection due to Cryptococcus neoformans developed in a 40 Year old immunocompetent and HIV negative man. Radiologic findings consisted in diffuse, bilateral reticular and nodular opacities. Bronchoscopy was normal and bronchoalveolar lavage showed numerous macrophages without associated pathogens. A thoracovideoscopy with an open lung biopsy showed numerous cryptococci, free in the alveoli or located within the macrophages. They were associated with an inflammatory infiltrate in the interalveolar spaces, predominantly composed of mononuclear cells. Ultrastructural study showed yeasts with numerous intracytoplasmic organites, a nucleus, a wall and a thick capsule. Pulmonary cryptococcosis is rare in immunocompetent hosts and can be difficult to diagnose since clinicoradiologic features observed in this cryptococcal infection mimic other infectious or neoplastic diseases.

Pulmonary cryptococcosis in immunocompetent patients

We analyzed the high-resolution CT (HRCT) findings of cryptococcosis in immunocompetent patients. The predominant manifestations were multiple nodules (n=6) and a single nodule (n=7). Regarding the pattern of multiple nodules, two cases of cavities or necrosis, four cases of surrounding centrilobular micronodules and five cases of "acinar" nodules were seen. No "tree-in-bud" appearance was detected. Five of seven cases of a single nodule were classified as polygonal, and two of them were round. Two cases accompanied micronodules and one case cavitation. Although no "tree-in-bud" appearance was observed, pulmonary cryptococcosis mimics tuberculosis.

Pulmonary Cryptococcosis in Nonimmunocompromised Patients

BACKGROUND

Cryptococcus neoformans can cause serious systemic infections requiring systemic antifungal therapy in immunocompromised hosts. However, isolated pulmonary cryptococcosis in nonimmunocompromised hosts has been reported to resolve spontaneously without treatment.

STUDY OBJECTIVE

s: To determine the role of antifungal therapy in the management of isolated pulmonary cryptococcosis in nonimmunocompromised hosts.

DESIGN

Retrospective study.

SETTING

Tertiary care, referral medical center

PATIENTS

Thirty-six nonimmunocompromised subjects with isolated pulmonary cryptococcosis who received diagnoses at the Mayo Clinic (Rochester, MN) from 1976 to 2001.

INTERVENTIONS

None.

MEASUREMENTS AND RESULTS

Of 42 nonimmunocompromised subjects with cryptococcal infections, 36 (86%) had isolated pulmonary cryptococcosis. The mean (+/- SD) age of these 36 patients was 61 +/- 15 years (range, 14 to 88 years), and the groups included 17 men (47%) and 19 women (53%). Twenty-four patients (67%) were symptomatic, and 12 patients (33%) were asymptomatic. The most common presenting symptoms were cough, dyspnea, and fever. Cultures of sputum and bronchial washings most commonly yielded the diagnosis. Cerebrospinal fluid examination was performed in 11 patients (31%) and was negative in all of them. Follow-up information was available on 25 patients (69%) with a median duration of 19 months (range, 1 to 330 months). Twenty-three of these patients (92%) had resolution of their disease (no treatment, 8 patients; surgical resection only, 6 patients; and antifungal therapy, 9 patients). The condition of the two remaining patients had improved. There was no documented treatment failure, relapse, dissemination, or death in any of these 25 patients.

CONCLUSIONS

Our findings suggest that an initial period of observation without the administration of antifungal therapy is a reasonable option for nonimmunocompromised subjects with pulmonary cryptococcosis in the absence of systemic symptoms or evidence of dissemination, as well as after surgical resection for focal cryptococcal pneumonia.

A ten-year-old boy with a pulmonary nodule secondary to Cryptococcus neoformans: case report and review of the literature

Pulmonary cryptococcosis is an uncommonly recognized disease of childhood. Among immunocompetent and non-HIV-infected individuals, pulmonary cryptococcosis may be asymptomatic or present with chronic, nondescript symptomatology. In this report we describe a 10-year-old with malignant fibrous histiocytoma of bone and a pulmonary nodule secondary to Cryptococcus neoformans. We use this case as a background to review the pediatric literature regarding pulmonary cryptococcosis and to discuss the utility of immunohistochemistry for diagnosis of this clinical entity.

Cryptococcus neoformans var. gattii in the koala (Phascolarctos cinereus): serological evidence for subclinical cryptococcosis

Cryptococcus neoformans var. gattii has been shown to have a strong association with eucalypts frequently used by koalas and, not surprisingly, it has been shown to colonize the nasal cavities of koalas. The progression from nasal colonization to tissue invasion is critical to understanding the pathogenesis of cryptococcosis in this species and provides a model for pathogenesis of cryptococcosis in other species. Cryptococcal antigenaemia was detected in twenty-eight healthy koalas from three different regions. This was interpreted as representing limited subclinical disease. One koala developed cryptococcal pneumonia 6 months after leaving the study, whereas another developed cryptococcal meningoencephalitis during the course of the study. Opportunistic necropsies on ten antigen-positive koalas resulted in discovery of small cryptococcal lesions in two (paranasal sinus and lung, respectively). Our data suggest that cryptococcal antigenaemia occurs commonly in koalas, especially in areas with a high environmental presence of C n. var. gattii. Subclinical disease appears most likely to manifest as a small focal lesion in the respiratory tract. Possible outcomes include elimination by an effective immune response, quiescence with possibility of later re-activation or direct progression to overt disease. Symptomatic and subclinical cases showed differences in levels of antigenaemia. The data presented have significant implications for koalas in captivity.

Conserved cAMP signaling cascades regulate fungal development and virulence

Two well characterized signal transduction cascades regulating fungal development and virulence are the MAP kinase and cAMP signaling cascades. Here we review the current state of knowledge on cAMP signaling cascades in fungi. While the processes regulated by cAMP signaling in fungi are as diverse as the fungi themselves, the components involved in signal transduction are remarkably conserved. Fungal cAMP signaling cascades are also quite versatile, which is apparent from the differential regulation of similar biological processes. In this review we compare and contrast cAMP signaling pathways that regulate development in the budding yeast Saccharomyces cerevisiae, the fission yeast Schizosaccharomyces pombe, and differentiation and virulence in the human pathogen Cryptococcus neoformans and the plant pathogen Ustilago maydis. We also present examples of interaction between the cAMP and MAP kinase signaling cascades in the regulation of fungal development and virulence.

Cyclic AMP-dependent protein kinase controls virulence of the fungal pathogen Cryptococcus neoformans

Cryptococcus neoformans is an opportunistic fungal pathogen that infects the human central nervous system. This pathogen elaborates two specialized virulence factors: the antioxidant melanin and an antiphagocytic immunosuppressive polysaccharide capsule. A signaling cascade controlling mating and virulence was identified. The PKA1 gene encoding the major cyclic AMP (cAMP)-dependent protein kinase catalytic subunit was identified and disrupted. pka1 mutant strains were sterile, failed to produce melanin or capsule, and were avirulent. The PKR1 gene encoding the protein kinase A (PKA) regulatory subunit was also identified and disrupted. pkr1 mutant strains overproduced capsule and were hypervirulent in animal models of cryptococcosis. pkr1 pka1 double mutant strains exhibited phenotypes similar to that of pka1 mutants, providing epistasis evidence that the Pka1 catalytic subunit functions downstream of the Pkr1 regulatory subunit. The PKA pathway was also shown to function downstream of the Galpha protein Gpa1 and to regulate cAMP production by feedback inhibition. These findings define a Galpha protein-cAMP-PKA signaling pathway regulating differentiation and virulence of a human fungal pathogen.