The trend of imported mycoses in Japan

Paracoccidioidomycosis: What We Know and What Is New in Epidemiology, Diagnosis, and Treatment

Paracoccidioidomycosis (PCM) is a systemic mycosis endemic to Latin America caused by thermodimorphic fungi of the genus Paracoccidioides. In the last two decades, enhanced understanding of the phylogenetic species concept and molecular variations has led to changes in this genus’ taxonomic classification. Although the impact of the new species on clinical presentation and treatment remains unclear, they can influence diagnosis when serological methods are employed. Further, although the infection is usually acquired in rural areas, the symptoms may manifest years or decades later when the patient might be living in the city or even in another country outside the endemic region. Brazil accounts for 80% of PCM cases worldwide, and its incidence is rising in the northern part of the country (Amazon region), owing to new settlements and deforestation, whereas it is decreasing in the south, owing to agriculture mechanization and urbanization. Clusters of the acute/subacute form are also emerging in areas with major human intervention and climate change. Advances in diagnostic methods (molecular and immunological techniques and biomarkers) remain scarce, and even the reference center’s diagnostics are based mainly on direct microscopic examination. Classical imaging findings in the lungs include interstitial bilateral infiltrates, and eventually, enlargement or calcification of adrenals and intraparenchymal central nervous system lesions are also present. Besides itraconazole, cotrimoxazole, and amphotericin B, new azoles may be an alternative when the previous ones are not tolerated, although few studies have investigated their use in treating PCM.

Pulmonary histoplasmosis diagnosed in a Japanese woman after traveling to central and South America: A case report

Histoplasmosis is a fungal infection caused by Histoplasma capsulatum, and Japan is considered a non-endemic area for histoplasmosis. Most patients diagnosed with histoplasmosis in the past usually have exposure to caves and bat guano with travel history to endemic areas. Therefore, travel history and risk activities should be comprehensively assessed when suspecting histoplasmosis because this important information may be overlooked. Although few, possibilities of indigenous cases have also been suggested. Moreover, it is assumed that the number of travelers and endemic mycoses has decreased with the recent coronavirus disease 2019 epidemic. However, clinicians should carefully consider the differential diagnosis of histoplasmosis for travelers traveling to endemic areas. In this case report, we describe an immunocompetent Japanese woman who developed histoplasmosis due to a history of travel to an endemic country. Our case report suggests that clinicians should not exclude histoplasmosis from the differential diagnosis even in the absence of risk features such as activities or immunodeficiencies during travel.

Pulmonary infections mimicking malignancy on bronchoscopy: A retrospective single-center study in Japan

BACKGROUND

Pulmonary infections can imitate pulmonary neoplasms. Pulmonary tuberculosis (TB) is a typical example of an infection that mimics cancer and results in unexpected exposure of healthcare workers to TB. A large number of patients with suspected lung malignancy are referred to cancer centers, although the epidemiology of the final diagnosis is unclear in Japan. This study aimed to determine the frequency and nature of pulmonary infections that imitate malignancy among patients with presumed lung cancer that is subsequently diagnosed as a pulmonary infection based on bronchoscopy findings. We also aimed to identify the prevalence of formerly undiagnosed pulmonary tuberculosis that could pose an occupational risk to healthcare workers.

METHODS

This single-center retrospective cross-sectional study included patients with suspected pulmonary malignancy who underwent bronchoscopy at a tertiary care cancer center in Japan between April 2017 and March 2020. Electronic medical records of the bronchoscopy database were reviewed to identify the final diagnoses recorded by physicians.

RESULTS

Among the 460 patients enrolled in the present study, 362 (78.7%) and 8 (1.7%) had primary or metastatic pulmonary lesions and benign lesions, respectively. Sixty-six patients (14.3%) had nonspecific findings or other pulmonary diseases. Infection was confirmed in 24 patients (5.2%). Mycobacterial infections (n = 16) were the most frequent infectious disease; four patients had TB and 12 had nontuberculous mycobacterial infections.

CONCLUSIONS

Despite the rare occurrence of TB in patients with suspected lung malignancy, healthcare workers should remain vigilant regarding the possibility of TB to prevent occupational exposure during invasive procedures such as routine bronchoscopy.

Seroprevalence of Antibodies Against Paracoccidioides Spp. in Captive Dolphins from Three Aquaria in Japan

The skin disease paracoccidioidomycosis ceti occurs in several dolphin species globally. Infection by the unculturable fungi Paracoccidioides brasilensis or other Paracoccidioides spp. results in chronic cutaneous and granulomatous lesions. In this study we used immunohistochemistry to investigate the seroprevalence of antibodies to Paracoccidioides spp. in captive dolphins from three aquaria in Japan. We had previously reported that there were serological cross-reactions for Paracoccidioides spp. with related species in the order Onygenales. We hypothesized that the degree of serological cross-reactions for Paracoccidioides spp. might be lower in areas, such as Japan, where the fungal diseases coccidiodomycosis and paracoccidiodomycosis are not endemic. Sera from 41 apparently healthy dolphins, including 20 Atlantic bottlenose dolphins (BD: Tursiops truncatus), 6 Indo-Pacific bottlenose dolphins (IPBD: Tursiops aduncus), 2 F1 generation of a cross between BD and IPBD (F1), 3 Pacific white-sided dolphins (PWD: Lagenorhynchus obliquidens), 2 pantropical spotted dolphins (PSD: Stenella attenuata), 6 false killer whales (FKW: Pseudorca crassidens), and 2 rough-toothed dolphins (RTD: Steno bredanensis) were investigated. Sera from three dolphins with paracoccidioidomycosis ceti were used as a positive control. The yeast-form cells of Paracoccidioides spp. in the cutaneous tissue sample derived from the first Japanese paracoccidioidomycosis ceti case were used as the antigen for the immunohistochemistry. Of the 41 dolphins tested, 61.0% had antibodies against Paracoccidioides spp. This indicates that dolphins of several species in Japanese aquaria have likely been exposed to the pathogen Paracoccidioides spp.

Timely Diagnosis of Histoplasmosis in Non-endemic Countries: A Laboratory Challenge

Human histoplasmosis is a fungal infection caused by the inhalation of microconidia of the thermally dimorphic fungi Histoplasma capsulatum. Autochthonous cases of histoplasmosis have been diagnosed in almost every country, but it is considered an endemic infection in specific areas of the world. Many of them are popular travel destinations or the source of migratory movements. Thus, the vast majority of the registered cases in non-endemic countries are imported. They correspond to people having been exposed to the fungus in endemic locations as immigrants, expatriates, transient workers or tourists, with reported cases also associated to organ donation. Misdiagnosis and delays in initiation of treatment are not uncommon in cases of imported histoplasmosis. They are associated to high fatality-rates specially in patients with compromised cellular immunity in which progressive disseminated forms develop. The diagnosis of this infection in non-endemic countries is hampered by the lack of clinical suspicion and a dearth of available diagnostic tools adequate to offer rapid and accurate results. Non-culture-based assays such as nucleic-acid amplification tests present as a suitable alternative in this situation, offering improved sensitivity and specificity, shortened turnaround time, and increased biosafety by avoiding culture manipulation. In non-endemic regions, molecular techniques are being used mainly in laboratories from countries that have registered an increase in the incidence of imported cases. However, the number of published techniques is limited and lack consensus. Efforts are currently under way to standardize nucleic acid amplification-based techniques for its implementation in areas registering a rising number of imported cases.

Re-drawing the Maps for Endemic Mycoses

Endemic mycoses such as histoplasmosis, coccidioidomycosis, blastomycosis, paracoccidioidomycosis, and talaromycosis are well-known causes of focal and systemic disease within specific geographic areas of known endemicity. However, over the past few decades, there have been increasingly frequent reports of infections due to endemic fungi in areas previously thought to be “non-endemic.” There are numerous potential reasons for this shift such as increased use of immune suppressive medications, improved diagnostic tests, increased disease recognition, and global factors such as migration, increased travel, and climate change. Regardless of the causes, it has become evident that our previous understanding of endemic regions for these fungal diseases needs to evolve. The epidemiology of the newly described Emergomyces is incomplete; our understanding of it continues to evolve. This review will focus on the evidence underlying the established areas of endemicity for these mycoses as well as new data and reports from medical literature that support the re-thinking these geographic boundaries. Updating the endemic fungi maps would inform clinical practice and global surveillance of these diseases.

Paracoccidioidomycosis of the Central Nervous System: CT and MR Imaging Findings

BACKGROUND AND PURPOSE

Paracoccidioidomycosis is a fungal infection mainly caused by the thermodimorphic fungus Paracoccidioides. The purpose of our study was to demonstrate the neuroimaging findings from 24 patients with CNS paracoccidioidomycosis.

MATERIALS AND METHODS

We performed a retrospective analysis focusing on the radiologic characteristics of CNS paracoccidioidomycosis. The 24 selected patients underwent MR imaging and/or CT, and the diagnosis was made by the presence of typical neuroimaging features, combined with fungus isolation, a serologic test, or the presence of disseminated disease.

RESULTS

Headache was the most common neurologic symptom, while the pseudotumoral form was the most common pattern. The number of lesions ranged from 1 to 11, with most localized on the frontal lobe with >2-cm lesions. CT showed mainly hypoattenuating lesions, whereas MR imaging demonstrated mainly hyposignal lesions on T1WI and T2WI. Furthermore, ring enhancement was present in most patients. The "dual rim sign" on SWI occurred in 100% of our patients with lesions of >2 cm.

CONCLUSIONS

The diagnosis of CNS paracoccidioidomycosis is difficult. Nevertheless, imaging examinations can play an important role in the diagnosis and evaluation of the disease.

Histoplasmosis among HIV-Infected Patients in Japan: a Case Report and Literature Review

Histoplasmosis is occasionally encountered in non-endemic countries owing to more frequent international travel and migration, as well as an increase in the number of vulnerable hosts (e.g., patients with cellular immunodeficiencies). However, the diagnosis of endemic mycoses may be challenging because of its rarity and the limited availability of diagnostic tests. We report a case of disseminated histoplasmosis in a human immunodeficiency virus (HIV)-infected Japanese man who had often travelled to histoplasmosis-endemic countries. We also reviewed the reported cases of HIV-associated histoplasmosis in Japan. To the best of our knowledge, this is the ninth case report of co-infection with Histoplasma and HIV in Japan and the second involving a Japanese patient. This case emphasizes the importance of noting the details of not only the present residence of patients, but also their previous residence and travels. If histoplasmosis is suspected, physicians should inform laboratory personnel that fungal cultures should be incubated for 6 weeks, and compliance with biosafety guidelines for handling the specimens should be practiced. Since death occurs in nearly 50% of HIV-associated histoplasmosis cases in Japan, early recognition, timely diagnosis, and appropriate treatment are mandatory.

Regional Differences in the Prevalence of Major Opportunistic Infections among Antiretroviral-Naïve Human Immunodeficiency Virus Patients in Japan, Northern Thailand, Northern Vietnam, and the Philippines

To identify regional differences in the distribution of opportunistic infections (OIs) among human immunodeficiency virus (HIV)-infected patients in Asia, the medical records of antiretroviral therapy (ART)-naïve patients who attended the following tertiary hospitals from 2003 to 2011 were reviewed: Nagoya Medical Center (NMC, Nagoya, Japan), Lampang Hospital (LPH, Lampang, northern Thailand), Bach Mai Hospital (BMH, Hanoi, northern Vietnam), and Philippine General Hospital (PGH, Manila, Philippines). Logistic regression analyses were performed to identify associations between country of origin and risk of major OIs. In total, 1,505 patients were included: NMC, N = 365; LPH, N = 442; BMH, N = 384; and PGH, N = 314. The median age was 32 years, and 73.3% of all patients were male. The median CD4 count was 200 cells/μL. Most patients at NMC and PGH were men who have sex with men. Injection drug users were most common at BMH (35.7%). Mycobacterium tuberculosis (TB) was most common at PGH (N = 75) but was rare at NMC (N = 4). Pneumocystis pneumonia (PCP) prevalence was highest at NMC (N = 74) and lowest at BMH (N = 13). Multivariable logistic regression showed increased odds of TB at PGH (adjusted odds ratio [aOR] = 42.2, 95% confidence interval [CI] = 14.6-122.1), BMH (aOR = 12.6, CI = 3.9-40.3), and LPH (aOR = 6.6, CI = 2.1-21.1) but decreased odds of PCP at BMH (aOR = 0.1, CI = 0.04-0.2) and LPH (aOR = 0.2, CI = 0.1-0.4) compared with those at NMC. The cryptococcosis risk was increased at LPH (aOR = 6.2, CI = 0.9-41.0) compared with that at NMC. Cytomegalovirus (CMV) retinitis prevalences were similar in all countries. OI prevalence remained high among ART-naïve patients in our cohort. The risks of TB, PCP, and cryptococcosis, but not CMV retinitis, differed between countries. Improved early HIV detection is warranted.

A case series of histoplasmosis patients with elevated serum soluble interleukin-2 receptor levels

Histoplasmosis is a common endemic mycosis that is usually asymptomatic but occasionally results in severe illness. Histoplasmosis and its causative agent, Histoplasma capsulatum, are found worldwide but rarely in Japan. In recent years, however, the number of histoplasmosis patients in Japan has increased. In addition, to our knowledge, there are no previous reports of increased serum soluble interleukin-2 receptor (sIL-2R) levels in patients with histoplasmosis. We report a case series of histoplasmosis in three Japanese temporary workers in Manzanillo, Mexico. All three patients developed a persistent high fever and general fatigue. Laboratory tests showed increased C-reactive protein levels and mild liver dysfunction. All patients also showed increased soluble interleukin-2 receptor (sIL-2R) levels. Chest computed tomography revealed multiple nodules in both lung fields. All patients were positive for serum anti-Histoplasma antibodies, and two patients were positive for Histoplasma on polymerase chain reaction tests. After treatment that included antifungals, their conditions gradually improved and laboratory data normalized. Although one patient developed respiratory failure, this patient recovered with antifungal therapy in combination with methylprednisolone. Serum sIL-2R levels in all patients gradually declined to normal levels, indicating their recovery from Histoplasma infection. From our experience with these patients, sIL-2R levels may be a useful biomarker for patients with histoplasmosis.

New Trends in Paracoccidioidomycosis Epidemiology

Paracoccidioidomycosis is a systemic fungal disease occurring in Latin America and more prevalent in South America. The disease is caused by the dimorphic fungus Paracoccidioides spp. whose major hosts are humans and armadillos. The fungus grows in soil and its infection is associated with exposure to the rural environment and to agricultural activities, with a higher risk in coffee and tobacco plantations. Population studies assessing the reactivity to Paracoccidioides spp. antigens by intradermal reaction or serological tests have detected previous subclinical infections in a significant proportion of healthy individuals living in various endemic countries. Paracoccidioidomycosis-disease is manifested by a small minority of infected individuals. The risk of developing the disease and its type of clinical form are related to the personal and life style characteristics of infected individuals, including genetic background, age, sex, ethnicity, smoking habit, alcohol drinking, and eventual cellular immunosuppression. Brazil, Colombia, Venezuela, Argentina, and Ecuador have endemic areas that had already been defined in the 20th century. The incidence of paracoccidioidomycosis can be altered by climate phenomena and mainly by human migration and occupation of poorly explored territories. In Brazil, the endemy tends to expand towards the North and Center-West around the Amazon Region.

EPIDEMIOLOGY OF PARACOCCIDIOIDOMYCOSIS

The epidemiological characteristics of paracoccidioidomycosis were reviewed and updated. The new endemic areas in Brazil were discussed in the section regarding the geographic distribution of the mycosis. Subclinical infection with Paracoccidioides brasiliensis was discussed on the basis of skin test surveys with antigens of the fungus, seroepidemiological studies, and disease cases outside Latin America. Large case series permitted a comparison of the prevalence of the mycosis in different regions, its estimated incidence and risk factors for the development of the disease. Aspects modulating the expression of the clinical forms of paracoccidioidomycosis are also presented. This review also deals with diseases associated with the mycosis, opportunistic paracoccidioidomycosis, lethality, mortality and infection and disease in animals.

Pulmonary Histoplasmosis in a Japanese Man Infected During Travel to Mexico and Management of His Wife's Condition: A Case Report

We report herein on the case of a 33-year-old Japanese man in whom an abnormal shadow was detected on chest radiography during a medical checkup after a 1-year-stay in Mexico. Chest computed tomography showed a nodule in the left lower lobe adjacent to the visceral pleura. Histopathologic examination of a thoracoscopic partial pulmonary resection specimen showed coagulation necrosis with a number of yeast-like forms on Grocott staining. In addition, serum anti-Histoplasma antibody positivity was detected with an enzyme-linked immunosorbent assay, and Histoplasma-specific nested real-time polymerase chain reaction results were positive in the pulmonary region. Finally, pulmonary histoplasmosis was diagnosed, and treatment with itraconazole was initiated. The patient's wife who had accompanied him to Mexico was asymptomatic and was not found to have histoplasmosis based on diagnostic imaging and serological findings. Although rare in Japan, histoplasmosis should be considered in the differential diagnosis of pulmonary lesions in patients who have returned from travel to endemic areas.

N-acetylated α-linked acidic dipeptidase is identified as an antigen of Histoplasma capsulatum

Histoplasmosis, one of the most important mycoses, needs to be diagnosed rapidly and accurately. The main method used to diagnose histoplasmosis is serological detection of antibodies to the Histoplasma capsulatum H and M antigens. Several other protein antigens have been reported in H. capsulatum; however, they have not been used for diagnosis. In this study, we explored novel antigens that were detected during H. capsulatum infection. We obtained a protein mixture from H. capsulatum yeast cells after vigorous mixing in a 0.1% Triton X-100 solution. From the resultant pool, we detected nine spots that reacted with sera from patients with histoplasmosis and identified eight seroactive proteins with mass spectrometry. The seroactive proteins were purified, and their antigenicities were tested with an enzyme-linked immunosorbent assay (ELISA). ELISA revealed that the titer of the patients' sera to N-acetylated α-linked acidic dipeptidase was significantly higher than those of healthy volunteers (P < 0.01). These data indicate that N-acetylated α-linked acidic dipeptidase of H. capsulatum is recognized as a major antigen during histoplasmosis.

Paracoccidioidomycosis

Paracoccidioidomycosis is an endemic systemic mycosis that predominates in southern Mexico, parts of Central America, and South America. It is caused by a dimorphic fungus and is generally acquired through the lungs, from where it disseminates. Paracoccidioidomycosis has different clinical manifestations that require differentiation with tuberculosis, Hodgkin disease, several systemic and subcutaneous mycoses, and squamous cell carcinoma. Diagnosis is made by finding the organism in a biopsy specimen and isolating it in fungal culture. Treatment includes sulfamethoxazole-trimethoprim for mild forms and itraconazole for moderate cases. Fluconazole and voriconazole can be used for meningeal involvement, and amphotericin B is indicated for severe disease.

Application of nested PCR for diagnosis of histoplasmosis

Histoplasmosis is a fungal infection that, although not endemic in Japan, has seen a rise in the number of Japanese cases since the mid-1980s. Diagnosis of the disease is not straightforward, and the main method of detection, fungal culture (which has biosafety-related issues), is of low sensitivity in general. Alternative methods that depend on antibody or antigen detection have had limited use. We have developed a histoplasmosis detection method based on PCR amplification of the Histoplasma capsulatum M antigen gene. We compared this method with fungal culture and serological diagnostic techniques. Among five cases that were finally diagnosed as histoplasmosis, the fungal culture method was only successful in identifying one such case. Although the presence of anti-H. capsulatum antibodies was confirmed in three cases, our PCR method identified four of five cases of histoplasmosis. The performance of our PCR method could not be compared with the antigen detection method, which is used in the United States but is not routinely used in Japan. However, the PCR method was shown to have high sensitivity and specificity for H. capsulatum. Although the number of histoplasmosis cases examined in this study was small, our data suggest that the molecular diagnosis technique has potential for increasing the reliability of histoplasmosis diagnosis when used in combination with established methods.

Endemic fungal infections in the Asia-Pacific region

Endemic mycoses are important fungal infections in their respective habitats. In the Asia-Pacific region, an accurate epidemiological picture of endemic mycoses is elusive; few epidemiological surveys have been performed, and limited laboratory facilities and experience with fungal infections have further hampered recognition of infection. However, pockets of endemicity do indeed exist, and endemic fungal infections can have a significant impact on public health. This article reviews the most common endemic mycoses in the Asia-Pacific region: histoplasmosis, penicilliosis, and sporotrichosis. Blastomycosis, which has been infrequently reported within the region, is also briefly discussed. Certain areas of the Asia-Pacific region are endemic for histoplasmosis; however, the ecologic niche for this infection remains unclear. Penicilliosis is restricted to Southeast and Eastern Asia, whereas sporotrichosis is encountered in tropical areas of the Asia-Pacific region linked to environmental reservoirs distinct from those seen in the Western world. Before the advent of acquired immune deficiency syndrome (AIDS), histoplasmosis and penicilliosis were only occasionally reported; however, the incidence of both mycoses has increased with the rise in the incidence of AIDS. Comprehensive studies are needed to fully assess the areas of endemicity and the impact of endemic mycoses in the Asia-Pacific region.

First report on the diagnosis and treatment of encephalic and urinary paracoccidioidomycosis in a cat

A male Persian cat was presented with persistent fever, anorexia, weakness, hypopyon, nystagmus, and intention tremors. The hemogram showed severe neutropenia and laboratory analysis on cerebrospinal fluid (CSF) smears revealed abundant yeast cells compatible with Paracoccidioides brasiliensis. Urinalysis demonstrated persistent funguria and an increased urine protein-to-creatinine ratio (UPC) in addition to mild azotemia. Long-term therapy with oral fluconazole was effective in controlling the nervous system signs. Funguria was resolved with subcutaneous administration of diluted amphotericin B in a large volume of saline solution for a period of 12 weeks during the second year after initial diagnosis. Throughout 5 years of treatment, no adverse effects were observed and tolerance to the drugs was normal. Due to development of progressive uremic syndrome the animal was euthanased. To the best of our knowledge, this report is the first clinical case described of a nervous and urinary system infection caused by the P brasiliensis in a cat.

Paracoccidioidomycosis in a Spanish missionary

Paracoccidioidomycosis is the most important systemic mycosis in South America. In Europe the disease is very rare and only found in returning travelers. Here we report on a 56-year-old Spanish missionary with respiratory symptoms but no other affected systems. Diagnosis was made based on serology and PCR for Paracoccidioides brasiliensis.

Applications of Loop-Mediated Isothermal Amplificaton Methods (LAMP) for Identification and Diagnosis of Mycotic Diseases: Paracoccidioidomycosis and Ochroconis gallopava infection

Loop-mediated isothermal amplification (LAMP) methods are now useful for the detection of a specific gene in infectious diseases, genetic diseases, and/or genetic disorders in the large number of medical fields, and it was recently introduced to fungal investigation. It is characterized by the use of four different primers specifically designed to recognize six distinct regions of the target gene, and the reaction process proceeds at a constant temperature using strand displacement reaction. Quickness and simplicity is the advantage of the method. Amplification and detection of gene can be completed in a single step, by incubating the mixture of samples, primers, DNA polymerase with strand displacement activity and substrates at a constant temperature. The method was applied to two fungal infections; paracoccidioidomycosis (PCM), a deep mycosis caused by Paracoccidioides brasiliensis and Ochroconis gallopava infection. For PCM a combination of F3, B3, FIP, and BIP primers designed from the partial sequence of P. brasiliensis gp43 gene was used. The PCR products amplified by the primer set; F3 and B3 showed species specificity for P. brasiliensis and the detection limit of the PCR was 100 fg of fungal genomic DNA. The specific DNA banding pattern of P. brasiliensis was detected in the clinical and nine-banded armadillo derived isolates, paraffin-embedded tissue sample or sputum from PCM patient. LAMP method was used also for the identification of O. gallopava by using species-specific primer sets based on the D1/D2 domain of the LSU rDNA sequence. The method successfully detected the gene from both fungal DNA derived from brains and spleens of experimentally-infected mice with O. gallopava and environmental isolates. In conclusion, LAMP method for PCM and O. gallopava seemed to be useful for identification, diagnosis or retrospective study with advantage in the quickness and simplicity procedure, but require strictly-controlled environments.

An outbreak of histoplasmosis among healthy young Japanese women after traveling to Southeast Asia

Histoplasmosis, caused by Histoplasma capsulatum, is an endemic mycosis in many countries of the world except for Japan. Outbreaks of histoplasmosis among Japanese people are very rare and are mainly imported by travelers. We report an outbreak of histoplasmosis among healthy Japanese people who traveled to a resort area in Southeast Asia. Three young Japanese women traveled to Langkawi island, Malaysia and stayed on the island for five days without visiting caves, a known reservoir of H. capsulatum. All three individuals developed flu-like symptoms with multiple nodule shadows on chest X rays or chest CT scans at around ten days after their return to Japan. Serum samples obtained from the three subjects were positive for anti-Histoplasma antibody and specific PCR for H. capsulatum on lung biopsy specimens and the serum from one patient was positive. The clinical course of all three patients improved without the use of anti-fungal agents and no recurrence has been confirmed. Clinical attendants should consider histoplasmosis when they see patients with flu-like symptoms with abnormal chest X-rays after visiting H. capsulatum endemic areas, especially Southeast Asia.

Is Histoplasma capsulatum a native inhabitant of Japan?

Histoplasmosis is an infectious disease caused by inhaling spores of the fungal pathogen H. capsulatum and in Japan is considered an imported mycosis. However, some patients in Japan with histoplasmosis have no history of traveling overseas nor of risk of occupational exposure to Histoplasma. To investigate the possibility of native distribution of Histoplasma in Japan, 187 bat guano samples from 67 bat-inhabited caves in 17 prefectures were collected. These were examined for H. capsulatum by culture and Histoplasma-specific PCR in three independent laboratories. No H. capsulatum was detected by either method, therefore H. capsulatum is unlikely to be present in bat guano in Japanese caves.

Fungal infection by Paracoccidioides brasiliensis mimicking bone tumor

Paracoccidioides brasiliensis infection causes a systemic mycosis originally described in Latin America but with current reports of worldwide distribution. The clinical presentation of paracoccidiodomycosis as an isolated long-bone lesion in children is quite unusual. This article describes a 10-year-old male with a lytic femoral bone lesion caused by P. brasiliensis infection that was first suspected of being of neoplasic etiology. The text also emphasizes the importance of including endemic fungal infections in the differential diagnosis of bone lesions.

Pulmonary histoplasmosis as an example of imported mycoses in Japan

As travel increases, histoplasmosis as an imported mycosis that has the potential to increase abruptly in Japan. A 56-year-old Japanese man who had been in Bolivia for 2 years complained of a dry cough. Chest computed tomography revealed multiple lesions in the right and left lower lobes of his lung that were difficult to diagnose and differentiate from advanced lung cancer. We performed surgical resection for biopsy by video-assisted thoracoscopic surgery. An intraoperative histopathological examination suggested a diagnosis of tuberculoma, but Mycobacterium tuberculosis DNA was not detected in the tumor tissue. Further histopathological examination, however, strongly suggested a diagnosis of histoplasmosis because multiple small, round yeast foci were observed after Grocott staining. The serological test was positive for anti-Histoplasma capsulatum and confirmed the diagnosis of pulmonary histoplasmosis. The postoperative course was uneventful, and fluconazole was administrated for 90 days after the operation. Concerning imported mycoses, physicians should be keep abreast of updated and detailed information.

Molecular epidemiology of canine histoplasmosis in Japan

A recent case of canine histoplasmosis, the first confirmed case of disseminated infection accompanied by carcinoma in Japan, was diagnosed by clinical characteristics, histopathological examination, chest radiographs, ocular fundoscopy and molecular biological data. The clinical manifestations were not limited to cutaneous symptoms but were referable to disseminated infection, similar to human autochthonous cases. The partial sequences of the internal transcribed spacer (ITS1/2) regions of the ribosomal DNA genes of this and other Japanese canine histoplasmosis strains were 99-100% identical to the sequence AB211551 derived from a human isolate in Thailand, and showed a close relationship to the sequences derived from Japanese autochthonous systemic and cutaneous human cases. The phylogenetic analysis of 97 sequences of the ITS1/2 region disclosed six genotypes. The genotypes derived from Japanese autochthonous human and dog cases belonged to the cluster consisting of Histoplasma capsulatum var. capsulatum and H. capsulatum var. farciminosum sequences, indicating that these varieties might cause not only cutaneous but also systemic histoplasmosis, regardless of their host species. The current status of the 3 varieties of Histoplasma capsulatum according to the host species remains a subject of further investigation.

Development of safety culture tube for molds and proposed procedure for collecting conidia or fixing strains to control fungal infection and allergy

The conidia of filamentous fungi can be easily blown into the air and tend to be contaminants in the laboratory environment. We developed a new "safety culture tube for fungi" to prevent biohazards and a procedure for collecting conidia for passage or fixing strains was proposed.

Trichosporon species isolated from guano samples obtained from bat-inhabited caves in Japan

Yeasts from caves have rarely been examined. We examined yeasts collected from bat guano samples from 20 bat-inhabited limestone and volcanic caves located in 11 prefectures in Japan. Of approximately 700 yeast-like colonies, nine Trichosporon species were recovered from 15 caves. Two of these were known species, and the remaining seven are potentially novel species, based on molecular phylogenetic analyses. In addition to Trichosporon species, identifiable strains of eight ascomycetous yeasts and one basidiomycetous yeast were recovered at frequencies of 5 to 35%. Our findings suggest that Trichosporon spp. are the major yeast species in bat guano in Japan and that bat guano is a potentially rich source of previously undescribed yeast species.

Management of intracranial fungal infections in patients with haematological malignancies

The incidence of, and mortality associated with, invasive fungal infections remains far higher than hoped. As a consequence of the overall increase in the incidence of such infections over time, the incidence of central nervous system (CNS) fungal infections is also increasing and, despite improvements in diagnostic techniques and the introduction of novel antifungal agents, therapy for CNS infections is still associated with discouragingly poor results. In patients with haematological malignancies, opportunistic infections with Candida or Aspergillus remain the most common infections affecting the CNS; however, opportunistic infections with less well-known fungi are becoming more common and must be considered in the differential diagnosis. New techniques for the early diagnosis of invasive fungal infections are emerging. Pharmacologic options for treating invasive fungal infections have also improved during the past few years, with new drugs becoming available that have broader antifungal spectra and better safety profiles. Other novel treatment approaches, such as combination therapy, are also being explored. Early investigations have produced encouraging results; however, large, prospective studies involving many patients are necessary to validate the widespread use of these approaches. This review analyses the existing guidelines for treatment of CNS fungal infections and the literature available on the use of new drugs to generate sets of recommendations for treatment of these life-threatening infections in patients with haematological malignancies.

High 18F-fluorodeoxyglocose uptake in adrenal histoplasmosis; a case report

Adrenal histoplasmosis is one of the most common adrenal granulomatous infections in endemic areas. Although CT or MRI findings of adrenal histoplasmosis have been documented, there are no reports regarding 18F-fluorodeoxyglocose (FDG) positron emission tomography (PET) findings. We report a case of bilateral adrenal histoplasmosis showing a significantly high uptake of 18F-fluorodeoxyglocose on PET study. Adrenal histoplasmosis should be considered as one of the differential diagnoses in cases of adrenal tumors with intense FDG uptake, even in non-endemic areas.

Pulmonary coccidioidomycosis that formed a fungus ball with 8-years duration

Coccidioidomycosis, caused by inhaling Coccidioides immitis, is a mycosis imported from endemic regions including the southwestern United States. C. immitis is so virulent that even a short-term stay in the endemic area can provide a chance for infection. Here, we report a 33-year-old Japanese man with formation of a fungus ball inside the pulmonary cavity secondary to coccidioidomycosis with a duration of 8 years, which is considered rare. He was infected with C. immitis in the United States in 1996. A nodule remained in the lung, which later cavitated with fungus ball formation. We identified Coccidioides immitis in the cultured specimen from the cavity and serum antibodies against it. We performed a lobectomy in 2003 since anti-fungal treatment was only temporarily effective. He is still free of disease 6 months later.

Central nervous system paracoccidioidomycosis: diagnosis and treatment

BACKGROUND

Paracoccidioidomycosis (PCM) is a systemic mycosis caused by Paracoccidioides brasiliensis. The involvement of the central nervous system (CNS) in paracoccidioidomycosis is higher than previously thought and 2 clinical presentations have been reported, meningitis and pseudotumoral.

METHODS

Twenty medical records of patients with CNS paracoccidioidomycosis treated from 1986 to 2003 were analyzed. The follow-up ranged from 1 to 18 years (mean = 8.9 +/- 4.2).

RESULTS

Besides CNS paracoccidioidomycosis, all patients but one had the chronic systemic form and the pseudotumoral clinical presentation was the most frequent. Based on computed tomography scan findings, 4 image patterns were identified: low-density lesion with ring enhancement, lesion with calcification and ring enhancement, multiloculated low-density lesion with ring enhancement, and diffuse subarachnoid enhancement. The magnetic resonance imaging was performed in 3 patients and showed subarachnoid enhancement in 1 patient and heterogeneous lesion with ring enhancement in 2 patients. Eleven patients were submitted to medical treatment and 9 needed neurosurgical treatment; ventriculoperitoneal shunts in 4 patients, brain lesions resection in 3 patients, and partial resection of spinal cord lesions in 2 patients. Eleven patients had excellent outcome, 4 patients died, 3 are in good clinical condition with residual pulmonary dysfunction, and 1 patient was lost to follow-up.

CONCLUSIONS

The diagnosis of paracoccidioidomycosis with involvement of the CNS is difficult and clinical suspicion is a key point to achieve the correct diagnosis. Patients with early diagnosis have a favorable outcome with clinical or surgical treatment.