Donor-derived endemic mycoses after solid organ transplantation: A review of reported cases

BACKGROUND

Donor-derived endemic mycoses are infrequently reported. We summarized the clinical characteristics and outcomes of these infections to provide guidance to transplant clinicians.

METHODS

Multiple databases were reviewed from inception through May 31, 2023 using endemic fungi as key words (e.g., Coccidioides, histoplasma, blastomyces, talaromyces, paracoccidioides). Only donor-derived infections (DDI) were included.

RESULTS

Twenty-four cases of DDI were identified from 18 published reports; these included 16 coccidioidomycosis, seven histoplasmosis, and one talaromycosis. No cases of blastomycosis and paracoccidiodomycosis were published. The majority were male (17/24,70.8%). Half of the cases were probable (12/24, 50%), seven were possible (29.2%), and only five were proven DDI (20.8%). Donor-derived coccidioidomycosis were observed in kidney (n = 11), lung (n = 6), liver (n = 3), heart (n = 2) and combined SOT recipients (1 KP, 1 KL) at a median time of .9 (range .2-35) months after transplantation. For histoplasmosis, the majority were kidney recipients (6 of 7 cases) at a median onset of 8 (range .4-48) months after transplantation. The single reported possible donor-derived talaromycosis occurred in a man whose organ donor had at-risk travel to Southeast Asia. Collectively, the majority of donors had high-risk exposure to Coccidioides (9/11) or Histoplasma sp. (6/6). Most donor-derived endemic mycoses were disseminated (18/24, 75%), and mortality was reported in almost half of recipients (11/24, 45.8%).

CONCLUSION

Donor-derived endemic mycoses are often disseminated and are associated with high mortality. A detailed evaluation of donors for the potential of an undiagnosed fungal infection prior to organ donation is essential to mitigate the risk of these devastating infections.

African histoplasmosis in a Guinea Bissau patient with HIV-2: Case report and review

African histoplasmosis is the relatively unknown infection by Histoplasma capsulatum var. duboisii. It is endemic to Central and West Africa, generally involving the skin with potential for systemic dissemination, and has been described mainly in immunocompetent hosts. We present the case of a 30-year-old Bissau-Guinean man with HIV-2 infection known for 16 years, irregularly treated, admitted with two weeks of fever, diarrhoea and cutaneous lesions. Examination revealed multiple subcutaneous nodes, Molluscum contagiosum-like lesions, generalized lymphadenopathy and painful palpation of the left iliac fossa. Laboratory tests showed severe nonhaemolytic anaemia and CD4+ count of 9/mm3, with normal creatinine and hepatic enzymes. Chest roentgenogram was unremarkable and a research for Mycobacterium tuberculosis by GeneXpert® was negative. Nonetheless, given the lack of further diagnostic tools, a presumptive diagnosis of disseminated tuberculosis was made, and the patient was started on tuberculostatic and antiretroviral drugs. Despite initial improvement, a national shortage of antiretrovirals precluded further treatment, with worsening of the clinical picture, namely an increase in the number and dimensions of the skin lesions. An excisional biopsy of a subcutaneous nodule revealed Histoplasma capsulatum var. duboisii. Unfortunately, due to the unavailability of antifungals, the patient died one week later. To our best knowledge, this is the first confirmed case of an HIV infected patient with African histoplasmosis in Guinea-Bissau.

Diagnostic accuracy cohort study and clinical value of the Histoplasma urine antigen (ALPHA Histoplasma EIA) for disseminated histoplasmosis among HIV infected patients: A multicenter study

Background

The Histoplasma urine antigen (HUAg) is the preferred method to diagnose progressive disseminated histoplasmosis (PDH) in HIV patients. In 2007, IMMY ALPHA Histoplasma EIA was approved for clinical for on-site use, and therefore useful for regions outside the United States. However, ALPHA-HUAg is considered inferior to the MVista-HUAg which is only available on referral. We aim to evaluate the diagnostic accuracy of ALPHA-HUAg.

Methodology/Principal findings

We conducted a multicenter, prospective, diagnostic test study in two secondary and eight tertiary-care facilities in Mexico. We included HIV patient with PDH suspicion and evaluated ALPHA-HUAg diagnostic accuracy using as reference standard the Histoplasma capsulatum growth on blood, bone marrow, and tissue cultures or compatible histopathologic exam (PDH–proven). We evaluated the results of 288 patients, 29.5% (85/288; 95% confidence interval [CI], 24.3–35.1) had PDH. The sensitivity of ALPHA-HUAg was 67.1% (95% CI, 56–76.8%) and the specificity was 97.5% (95% CI, 94.3%-99.1%). The positive likelihood ratio was 27.2 (95% CI; 11.6–74.4). In 10.5% of the PDH–proven patients, a co-existing opportunistic infection was diagnosed, mostly disseminated Mycobacterium avium complex infection.

Conclusions/Significance

We observed a high specificity but low sensitivity of IMMY-HUAg. The test may be useful to start early antifungals, but a culture-based approach is necessary since co-infections are frequent and a negative IMMY-HUAg result does not rule out PDH.

Histoplasmosis is an endemic mycosis in many regions of Latin America. In the HIV population it manifests as progressive disseminated histoplasmosis (PDH), an entity hard to diagnose since the causative fungi—Histoplasma capsulatum—is slow growing and requires advance biosafety for its handling. As an alternative, the diagnosis can be made by detecting the histoplasma urinary antigen, but only one kit is commercially available outside the US. We evaluated this kit (IMMY ALPHA Histoplasma EIA) among HIV patients with suspected and found a high specificity but low sensitivity (i.e., a positive histoplasma urine antigen is almost unequivocal, but a negative result does not rule out the PDH). However, we believe the test is useful since the positive likelihood rates show that a patient with PDH is 27 times more likely to have an IMMY-HUAg positive result; this may allow early targeted treatment.

Outbreak of Severe Histoplasmosis Among Tunnel Workers-Dominican Republic, 2015

Background

Histoplasmosis is a fungal infection associated with exposure to bat guano. An outbreak of an unknown severe febrile illness occurred among tunnel workers in the Dominican Republic, and resulted in several deaths. We conducted an investigation to confirm etiology and recommend control measures.

Methods

A case was defined as fever and ≥2 symptoms consistent with histoplasmosis in a tunnel worker, July-September 2015. We interviewed workers and family members, reviewed medical records, tested serum and urine for Histoplasma antigen/antibody, and conducted a cohort study to identify risk factors for histoplasmosis and severe infection (intensive care).

Results

A crew of 36 male workers removed large amounts of bat guano from tunnels without respiratory protection for a median of 24 days per worker (range, 1-25 days). Median age was 32 years (range, 18-62 years); none were immunocompromised. Thirty (83%) workers had illness that met the case definition, of whom 28 (93%) were hospitalized, 9 (30%) required intensive care, 6 (20%) required intubation, and 3 (10%) died. The median time from symptom onset to antifungal treatment was 6 days (range, 1-11 days). Twenty-two of 34 (65%) workers had laboratory evidence of infection.

Conclusions

Severe illnesses and death likely resulted from exposure to large inocula of Histoplasma capsulatum spores in an enclosed space, lack of respiratory protection, and delay in recognition and treatment. Clinician education about histoplasmosis, improved laboratory capacity to diagnose fungal infections, and occupational health guidance to protect workers against endemic fungi are recommended in the Dominican Republic.

Concomitant disseminated histoplasmosis and disseminated tuberculosis after tumor necrosis factor inhibitor treatment: a case report

BACKGROUND

Tumor necrosis factor antagonist inhibitors have transformed the approach to patients with severe autoimmune conditions, such as rheumatoid arthritis. Although the therapy can be highly effective, TNF-α inhibitors are associated with an increased risk of opportunistic infections.

CASE PRESENTATION

Here, we report a case of concomitant disseminated histoplasmosis and tuberculosis in a 65-year-old female with rheumatoid arthritis treated with TNF-α inhibitor. Both conditions can be found in disseminated form in immunosuppressed hosts, but co-infection is rare with only a few cases having been reported, to our knowledge, all in HIV patients.

CONCLUSIONS

This case posed a considerable challenge for diagnosis and treatment due to the unusual disseminated co-infection, the overlapping symptoms, and the interactions between medications.

A 15-year-old boy with severe combined immunodeficiency, fungal infection, and weight gain

Hematopoietic stem cell transplantation (HSCT) outcomes in X-linked severe combined immune deficiency are most effective when performed with patients <3 months of age and without coexisting morbidity, and with donor cells from a matched sibling. Even under such favorable circumstances, outcomes can be suboptimal, and full cellular engraftment may not be complete, which results in poor B or natural killer cell function. Protein losing enteropathies can accompany persistent immune deficiency disorders with resultant low serum globulins (immunoglobulin A [IgA], IgG, IgM) and lymphopenia. Patients with immune disorders acquire infections that can be predicted by their immune dysfunction. Fungal infections are typically noted in neutropenic (congenital or acquired) and T-cell deficient individuals. Coexisting fungal infections are rare, even in hosts who are immunocompromised, and they require careful evaluation. Antifungal treatment may result in drug-drug interactions with significant complications.

[Histoplasmosis: the multiple sides of an uncommon disease]

Disseminated histoplasmosis is an invasive fungal infection documented in patients with impaired cellular immunity coming from endemic areas (America, Asia, Africa). We report two cases of disseminated histoplasmosis in AIDS patients paradigmatic of the multifaceted nature of the disease, which may be an expression either of an advanced state of immunosuppression or the immune reconstitution inflammatory syndrome (IRIS).

Chronic Progressive Disseminated Histoplasmosis in a Mexican Cockfighter

We present illustrative images from a Mexican 58-year-old man who had the occupation of cockfighting from childhood and presented with chronic progressive disseminated histoplasmosis with primarily cutaneous manifestations.

Histoplasmosis in patients with human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS): multicenter study of outcomes and factors associated with relapse

Although discontinuation of suppressive antifungal therapy for acquired immunodeficiency syndrome (AIDS)-associated histoplasmosis is accepted for patients with immunologic recovery, there have been no published studies of this approach in clinical practice, and minimal characterization of individuals who relapse with this disease. We performed a multicenter retrospective cohort study to determine the outcome in AIDS patients following discontinuation of suppressive antifungal therapy for histoplasmosis. Ninety-seven patients were divided into a physician-discontinued suppressive therapy group (PD) (38 patients) and a physician-continued suppressive therapy group (PC) (59 patients). The 2 groups were not statistically different at baseline, but at discontinuation of therapy and at the most recent follow-up there were significant differences in adherence to therapy, human immunodeficiency virus (HIV) RNA, and urinary Histoplasma antigen concentration. There was no relapse or death attributed to histoplasmosis in the PD group compared with 36% relapse (p < 0.0001) and 5% death (p = 0.28) in the PC group. Relapse occurred in 53% of the nonadherent patients but not in the adherent patients (p < 0.0001). Sixty-seven percent of patients with initial central nervous system (CNS) histoplasmosis relapsed compared to 15% of patients without CNS involvement (p = 0.0004), which may be accounted for by nonadherence. In addition, patients with antigenuria above 2.0 ng/mL at 1-year follow-up were 12.82 times (95% confidence interval, 2.91-55.56) more likely to relapse compared to those with antigenuria below 2.0 ng/mL. Discontinuation of antifungal therapy was safe in adherent patients who completed at least 1 year of antifungal treatment, and had CD4 counts >150 cells/mL, HIV RNA <400 c/mL, Histoplasma antigenuria <2 ng/mL (equivalent to <4.0 units in second-generation method), and no CNS histoplasmosis.

Esophageal histoplasmosis in a renal allograft recipient

Histoplasmosis is a progressive granulomatous disease caused by the intracellular dimorphic fungus Histoplasma capsulatum. We report a rare case of esophageal histoplasmosis in a renal allograft recipient. A 55-year-old male who received a live, unrelated renal allograft 20 years ago presented with complaints of recurrent fever for ten to 12 months, weight loss over six months, progressive dysphagia more for solids for five to six months and joint pain and swelling involving the bilateral metacarpo-phalangeal and proximal interphalangeal joints. Biopsy from the esophageal ulcers revealed dense inflammation infiltrated with lymphocytes and macrophages with clusters of strongly positive intracellular fungal spores with a clear area or "halo-like" zone suggestive of Histoplasma capsulatum invasion. The patient was treated with intravenous liposomal amphotericin B for ten days and later switched over to oral itraconazole. Repeated endoscopy revealed significant improvement of the lesions.

Prosthetic valve endocarditis caused by Histoplasma capsulatum: the first case report in Thailand

The authors report a rare case of fungal endocarditis caused by Histoplasma capsulatum in an immunocompetent woman with mitral valve prosthesis. The patient presented with chronic fever and embolic phenomenon. Transthoracic and transesophageal echocardiography revealed a mobile mass attached to mitral prosthetic valve and her blood cultures were negative for both bacteria and fungi. The diagnosis was made by presence of budding yeasts in the histopathological findings of the vegetation and recovery of H. capsulatum from tissue culture of the excised vegetation. The patient was improved after a 6-week course of amphotericin B. Fungal endocarditis caused by Histoplama capsulatum is rare but should be considered as a possible causative organism in culture-negative endocarditis. To our knowledge, this is the first case report of H. capsulatum endocarditis in Thailand.

[Fatal miliary tuberculosis in an HIV-infected Cameroon woman: disseminated histoplasmosis due to Histoplasma capsulatum capsulatum]

The purpose of this report is to describe the first Cameroonian case of disseminated histoplasmosis due to Histoplasma capsulatum capsulatum in association with HIV infection. The patient was a 34-year-old HIV1 infected woman. Diagnosis of histoplamosis was made in post-mortem. The similarity of the clinical symptoms with disseminated tuberculosis makes diagnosis of mycosis difficult. Active and effective care of histoplasmosis is urgently necessary for the HIV infected persons.

[Histoplasmosis updating]

Histoplasmosis, an infection caused by the fungus Histoplasma capsulatum, has been reported all over the world and is considered endemic in the American continent, including Cuba. This fungus grows on the soils contaminated with bird and bat excreta, where it produces a great number of microconidia that could cause the infection when they are inhaled. The clinical spectrum varies from asymptomatic infections to serious disseminated diseases involving one or many organ systems and affects mainly AIDS patients, patients with hematological neoplasias, transplant recipients or other immunosuppressed patients. The main risk groups include those individuals whose working activities make them be exposed to aerosols contaminated with H. capsulatum. Lab diagnosis is based on the microscopic observation, isolation and identification of the fungus in fluid or tissue samples of patients, and on specific antigen and antibodies detection. The molecular methods based on polymerase chain reaction have not been sufficiently defined, and they could be an important advance in the early diagnosis of this mycosis. Itraconazole is recommended for treatment of moderate, localized and chronic infection whereas amphotericin B is the drug of choice for disseminated and serious manifestations, particularly in its lipidic formulations. At present, histoplasmosis is considered one of the most important systemic mycoses in the Americas, and it is widely spread over all regions of Cuba.

[Colonic histoplasmosis as a diagnostic manifestation of AIDS]

We report the case of 48 year old female patient without a history of significance importance.(refuses blood transfusion). She complaint of diarrhea of four months of duration and weight loss of 8 kg. she added episodes of hematochezia and severe anemia requiring transfusion. An intrahemorrhagic colonoscopy was performed detecting three ulcerated lesions. First at 10 cm from the anus, one in transverse colon distal, another similar ulcer in the proximal transverse The biopsies showed ulcer granulation tissue, abundant macrophages with intracytoplasmic structures consistent with histoplasmosis. Tests showed no tuberculosis or intestinal parasitosis. HIV testing (ELISA and Western Blot) were positive. The CD4 (78 cells) and extrapulmonary histoplasmosis were the criteria defined stage AIDS. The extrapulmonary histoplasmosis defines stage IV in immunosuppressed patients with HIV. Lower gastrointestinal bleeding colonic ulcer secondary to Histoplasma is a rare form presentation as a diagnostic manifestation of AIDS.

Investigation of the cause of death in a gene-therapy trial

We present a case of disseminated histoplasmosis, complicated by retroperitoneal bleeding and leading to death, in a patient who was receiving systemic immunosuppressive therapy for rheumatoid arthritis and who was enrolled in a gene-therapy trial. This trial was designed to evaluate intraarticular delivery of a tumor necrosis factor alpha (TNF-alpha) antagonist, through an adeno-associated virus (AAV) type 2 delivery system, for inflammatory arthritis. The patient's receipt of concurrent anti-TNF-alpha therapy and other immunosuppressive therapy while she was living in an area where histoplasmosis was endemic was thought to be the most likely explanation for the infection; the evidence presented suggests that this fatal infection was unlikely to have been related to exposure to the agent administered in the gene-therapy trial. This case reinforces the importance of considering infectious complications, such as those from endemic mycoses, in patients receiving treatment with a TNF-alpha antagonist and the importance of having a well-designed monitoring plan when subjects in a research study become ill. (ClinicalTrials.gov number, NCT00126724.)

[Case of an HTLV-1 carrier complicated with chronic pulmonary histoplasmosis]

A 58-year-old man was admitted with complaints of pain in the right upper right side of the chest. Chest radiography and computed tomography (CT) revealed a cavitary lesion in the right upper lobe. A CT-guided percutaneous lung biopsy and transbronchial lung biopsy of this lesion did not yield a definitive diagnosis; therefore, we performed video assisted thoracic surgery (VATS). We also investigated various types of mycosis because he had several records of overseas travel. At a later day, the histoplasma immunodiffusion test showed positive results. We finally diagnosed pulmonary histoplasmosis based on the clinical course, CT and radiographic images and serological tests. Voriconazole improved the patient's subjective symptoms and laboratory findings. A positive reaction was obtained for anti-human T-cell leukemia virus type 1 (HTLV-1) antibody and the HTLV-1 carrier, confirming his immunodeficiency disorder. We raised the possibility that the development of pulmonary histoplasmosis might be associated with the HTLV-1 carrier.

A case of histoplasmosis mimicking tuberculosis

Drug resistance to Tuberculosis is an emerging problem but proper exhaustive workup needs to be done before confirming the diagnosis. The case of a 5 year old male child who presented with low grade fever and lymphadenopathy and was being treated with anti TB drugs with no satisfactory response is presented. A detail workup including a biopsy gave the diagnosis of histoplasmosis.

Sudden onset of verrucous plaques to the face and trunk: a case of cutaneous histoplasmosis in the setting of HIV

A 66-year-old Columbian man presented with a 15-day history of generalized weakness, cough, fever, and verrucous, ulcerating plaques of the face, upper chest and back, and arms. The patient proved to be HIV positive. Histopathologic examination showed a diffuse lymphocytic infiltrate coupled with a striking number of yeast forms within macrophages. The clinical presentation and histopathologic alterations are consistent with the diagnosis disseminated Histoplasma capsulatum. This case emphasizes the importance of increasing awareness of histoplasmosis in nonendemic areas as a result of the large subgroup of immunocompromised patients at risk. Disseminated histoplasmosis can be a treatable HIV complication if recognized early, though is unfortunately a harbinger for an overall poor prognosis.

Platelia Aspergillus assay for diagnosis of disseminated histoplasmosis

The Platelia Aspergillus assay tested positive in 8 of 11 patients with disseminated histoplasmosis. While other available methods for diagnosis have several drawbacks, this cross-reactivity is particularly valuable in the perspective of practitioners outside the USA who cannot use the test detecting antigen of Histoplasma capsulatum.

Nodular pulmonary histoplasmosis in Cushing's disease: a case report and literature review

Opportunistic infections are well documented in states of steroid excess. To our knowledge, histoplasmosis has not been previously reported in Cushing's disease, and has rarely been reported in patients with exogenous glucocorticoid use. We report a novel presentation of Histoplasmosis as pulmonary nodules in a patient with Cushing's disease. A 45-year-old man with a pituitary macroadenoma and Cushing's disease was treated with transsphenoidal hypophysectomy and radiation therapy. He was receiving Ketoconazole and basal steroid replacement, when he presented with dyspnea. Chest radiograph showed nodular lesions and subsequent biopsy revealed Histoplasma capsulatum. Itraconazole was administered and the patient recovered. The case not only demonstrates the protean manifestations of Histoplasmosis in patients with glucocorticoid excess but it also emphasizes the importance of intensive control of the hypercortisolemia in achieving a favorable outcome.

Detection of histoplasma antigen by a quantitative enzyme immunoassay

The second-generation Histoplasma antigen immunoassay is semiquantitative, expressing results as a comparison to a negative control, which requires repeat testing of the prior specimen with the current specimen to accurately determine a change in antigen. Reporting results in this manner often is confusing to the ordering physician and laboratory. Development of a quantitative assay could improve accuracy, reduce interassay variability, and eliminate the need to test the prior sample with the current sample in the same assay. Calibrators with known concentrations of Histoplasma antigen were used to quantitate antigen in specimens from patients with histoplasmosis and from controls. Samples from cases of disseminated histoplasmosis or other mycoses and controls were tested to evaluate the performance characteristics of the quantitative assay. Paired specimens were evaluated to determine if quantitation eliminated the need to test the current and prior specimens in the same assay to assess a change in antigen. The sensitivity in samples from patients with AIDS and disseminated histoplasmosis was 100% in urine and 92.3% in serum. Cross-reactions occurred in 70% of other endemic mycoses, but not in aspergillosis. Specificity was 99% in controls with community-acquired pneumonia, medical conditions in which histoplasmosis was excluded, or healthy subjects. A change in antigen level categorized as an increase, no change, or decrease based on antigen units determined in the same assay agreed closely with the category of change in nanograms/milliliter determined from testing current and prior specimens in different assays. Sensitivity, specificity, and interassay precision are excellent in the new third-generation quantitative Histoplasma antigen immunoassay.

Tumor necrosis factor-alpha and host resistance to the pathogenic fungus, Histoplasma capsulatum

Tumor necrosis factor-alpha (TNF-alpha) is a multifunctional cytokine that is critically important in host defenses to a number of pathogenic microbes. Among those, this cytokine is necessary for control of infection with the pathogenic fungus, Histoplasma capsulatum. Antagonism of endogenous cytokine is associated with an enhanced susceptibility to histoplasmosis in both mice and humans. The mechanisms by which TNF-alpha modulates the protective immune response will be discussed.

Histoplasmosis diseminada con lesiones limitadas a la laringe en un paciente con SIDA. Reporte de un caso y revisión de la literatura

Histoplasmosis is an endemic and systemic mycosis, caused by the dimorphic fungus Histoplasma capsulatum var capsulatum. Disseminated disease in immunocompromised patients generally results from the reactivation of latent foci after a prolonged period of asymptomatic infection. We report a case of laryngeal histoplasmosis as the unique clinical manifestation of a progressive form of the disease in a patient with advanced HIV/AIDS disease. Histopathological analysis of laryngeal biopsy smears revealed granulomas containing Histoplasma-like organisms. Treatment with amphotericin B followed by itraconazole resulted in complete remission of laryngeal lesions. To our knowledge, this is the third case report of laryngeal histoplasmosis in a patient with AIDS.

Oral histoplasmosis after radiation therapy for laryngeal squamous cell carcinoma

Histoplasmosis is a usually asymptomatic deep fungal infection of tropical origin with respiratory entry and possible oral, pharyngeal, or metastatic localization. The condition represents an important imported systemic mycosis with oral involvement. We report the case of a patient who developed an oropharyngeal reactivation of a latent Histoplasma infection after receiving local antitumoral radiation therapy of the neck. H capsulatum was shown to be present in the lesion by both histopathology and staining, and was deduced to be the causative organism of the disease.

Fungal infections in solid organ transplantation

Fungal infections in solid organ transplant recipients continue to be a significant cause of morbidity and mortality. Candida spp. and Aspergillus spp. account for most invasive fungal infections. The incidence of fungal infection varies with type of solid organ transplant. Liver transplant recipients have highest reported incidence of candida infections while lung transplant recipients have highest rate of Aspergillus infections. Recent epidemiological studies suggest the emergence of resistant strains of candida as well as mycelial fungi other than Aspergillus in these patients. The current review incorporates the recent changes in the epidemiology of fungal infections in solid organ transplant recipients and highlights the newer data on the diagnosis, prophylaxis and treatment of fungal infections in these patients.

Spinal intramedullary histoplasmosis as the initial presentation of human immunodeficiency virus infection: case report

OBJECTIVE

Spinal intramedullary histoplasmosis is an extremely rare condition. We report a case of isolated intramedullary histoplasmosis as the initial manifestation of human immunodeficiency virus (HIV) infection.

CLINICAL PRESENTATION

A 27-year-old man presented with a rapidly progressive paraparesis. Magnetic resonance imaging scans revealed an enhancing lesion at C7-T1 with edema extending as far as the cervicomedullary junction. He improved with steroid medications.

INTERVENTION

The patient underwent laminectomy and biopsy of the lesion. The diagnosis of histoplasmosis was made by histology, culture, and polymerase chain reaction identification of fungal deoxyribonucleic acid. The patient did not have disseminated histoplasmosis. Subsequent to the biopsy, the patient was discovered to have HIV infection.

CONCLUSION

The isolated spinal histoplasmosis lesion thus represented the initial presentation of HIV infection. Management of the case and diagnostic issues are discussed.

Disseminated histoplasmosis presenting as thrombotic microangiopathy

BACKGROUND

Thrombotic microangiopathies (TMA) are systemic vasoocclusive disorders associated with significant morbidity and mortality. Rapid and reliable diagnosis of TMA is critical. The diagnosis is complicated by a lack of objective and sensitive laboratory testing as well as multiple concurrent diseases, including infectious processes.

CASE STUDY

We report two cases of disseminated histoplasmosis associated with TMA manifestations in renal transplant recipients, including one patient with histologically documented renal microthrombi; both patients were referred for plasma exchange. After the diagnosis of histoplasmosis, the treatment plan was changed to antifungal medications, reduced immuno-suppression, and supportive care, with progressive resolution of TMA manifestations.

CONCLUSION

TMA occurs in transplant populations in association with infections, medications, and other factors. Appropriate management includes recognition and treatment of possible etiological factors. Disseminated histoplasmosis should be considered in transplant patients presenting with TMA.

Histoplasmosis among human immunodeficiency virus-infected people in Europe: report of 4 cases and review of the literature

We reviewed the clinical, microbiologic, and outcome characteristics of 72 patients with human immunodeficiency virus (HIV)-associated histoplasmosis (4 newly described) reported in Europe over 20 years (1984-2004). Seven cases (9.7%) were acquired in Europe (autochthonous), whereas the majority involved a history of travel or arrival from endemic areas. The diagnosis of progressive disseminated histoplasmosis (PDH) was made during life in 63 patients (87.5%) and was the acquired immunodeficiency syndrome (AIDS)-presenting illness in 44 (61.1%). Disease was widespread in 66 patients (91.7%) and localized in 6 (8.3%), with the skin being the most frequent site of localized infection. Overall skin involvement was reported in 47.2% of the patients regardless of whether histoplasmosis was acquired in Africa or South America. Reticulonodular or diffuse interstial infiltrates occurred in 52.8%. The diagnosis was made during life by histopathology plus culture in 44 patients (69.8%), histopathology alone in 18 (28.5%), and culture alone in 1 (1.5%). During the induction phase amphotericin B and itraconazole (74.6%) were the single most frequently used drugs. Both drugs were also used either in combination (10.2%) or in sequential therapy (11.8%). Cumulative mortality rate during the induction phase of treatment was 15.2%. Overall, 37 patients died (57.8%); death occurred early in the course in 18 (28.1%). Seven of 40 patients (17.5%) who responded to therapy subsequently relapsed. Autopsy data in 13 patients confirmed the widespread disseminated nature of histoplasmosis (85%) among AIDS patients with a median of 4.5 organs involved. The results of the present report highlight the need to consider the diagnosis of PDH among patients with AIDS in Europe presenting with a febrile illness who have traveled to or who originated from an endemic area.

Protective Antibodies and Endemic Dimorphic Fungi

The host response to infection is the outcome of a complex interaction between a microbe and a host's innate and adaptive immune system. In this context, the role of antibody in the endemic mycoses is relatively poorly understood. Recently, a monoclonal antibody to a cell surface protein has been shown to be protective in a murine histoplasmosis model. The findings with Histoplasma capsulatum may provide a paradigm for antibody protection against endemic fungi. This paper reviews the recent data on protective antibody in histoplasmosis and previous data supporting a role for antibody in protective responses in other dimorphic fungi.

Two outbreaks of occupationally acquired histoplasmosis: more than workers at risk

OBJECTIVE

The objective of this study was to determine the etiology and risk factors for acute histoplasmosis in two outbreaks in Illinois among laborers at a landfill in 2001 and at a bridge reconstruction site in 2003.

DESIGN

We performed environmental investigations during both outbreaks and also performed an analytic cohort study among bridge workers.

PARTICIPANTS

Workers at the landfill during May 2001 and those at the bridge site during August 2003 participated in the study. At the landfill, workers moved topsoil from an area that previously housed a barn; at the bridge, workers observed bat guano on bridge beams.

EVALUATIONS/MEASUREMENTS

We defined a case by positive immunodiffusion serology, a > or = 4-fold titer rise in complement fixation between acute and convalescent sera, or positive urinary Histoplasma capsulatum (HC) antigen. Relative risks (RR) for disease among bridge workers were calculated using bivariate analysis.

RESULTS

Eight of 11 landfill workers (73%) and 6 of 12 bridge workers (50%) were laboratory-confirmed histoplasmosis cases. Three bridge workers had positive urinary HC antigen. At the bridge, seeing or having contact with bats [RR = 7.0; 95% confidence interval (CI), 1.1-43.0], jack-hammering (RR = 4.0; 95% CI, 1.2-13.3), and waste disposal (RR = 4.0; 95% CI, 1.2-13.3) were the most significant job-related risk factors for acquiring histoplasmosis.

CONCLUSIONS

Workers performing activities that aerosolized topsoil and dust were at increased risk for acquiring histoplasmosis. Relevance to professional and clinical practice: Employees should wear personal protective equipment and use dust-suppression techniques when working in areas potentially contaminated with bird or bat droppings. Urinary HC antigen testing was important in rapidly identifying disease in the 2003 outbreak.

[Disseminated histoplasmosis: an atypical ulcerous form in an HIV-infected patient]

INTRODUCTION

Histoplasma capsulatum var capsulatum is a dimorphic fungi predominating on the American continent. It is responsible for disseminated histoplasmosis associated with AIDS. The presentation in the form of cutaneous ulceration is uncommon and misleading.

OBSERVATION

A 25 year-old man presented with 3 ulcerations, of 2 to 4 cm in diameter, localized on the lower lip and knees. The patient exhibited fever, alteration in his general status of health and a pulmonary interstitial syndrome. He was seropositive for the human immunodeficiency syndrome (HIV). His lymphocyte CD4+ level was of 1/mm3. Diagnosis of histoplasmosis was established by direct examination and culture of the cutaneous ulcerations and bronchoalveolar washing fluid.

DISCUSSION

The clinical aspect of cutaneous localizations of disseminated histoplasmosis is usually multiple, disseminated, papular or nodular-type lesions. Ulcerations represent less than 20% of the cases described. In our patient, the aspect of the lesions at first evoked cutaneous leishmaniosis. Direct mycological examination followed by culture confirmed the final diagnosis.

[Histoplasmosis in a renal transplant patient]

The case of a Spanish kidney transplant patient who developed disseminated histoplasmosis approximately one year and a half after transplantation without having previously visited or travelled to endemic areas of histoplasmosis is presented. To our knowledge this is the first case of this disease in a kidney transplant patient in Spain without epidemiologic antecedent. The study of anti-histoplasm antibodies by complement fixation of the donor and recipient did not safely clarify the mechanism of contagion.

[Interruption of antifungal secondary prophylaxis in AIDS-related histoplasmosis]

The clinical data of 21 patients, suffering AIDS-related histoplasmosis, who were able to interrupt antifungal secondary prophylaxis, after achieving a partial restoration of the cell mediated immunity by HAART administration, are presented. They were 16 males and five females, whose ages varied between 32 and 54 years (mean = 38.5 years). All of them presented disseminated progressive forms of histoplasmosis, with multiple locations (skin, mucous membranes, liver, spleen, lymph nodes and lungs). The majority of the cases suffered other concomitant diseases (specially tuberculosis and Kaposi sarcoma), 66.6 % of the patients had less than 50 CD4+ cells/microl at the start of treatment and the average viral burden was 278,385 RNA copies/ml. The initial treatment consisted in 400 mg/day of itraconazole, by oral route, in 14 cases and the remaining seven patients were treated with amphotericin B, intravenously, at a daily dose of 0.7 mg/kg of body weight. One patient who did not tolerate amphotericin B and presented a partial response to itraconazole, was treated with posaconazole orally at a daily dose of 800 mg. Fourteen patients received oral itraconazole at a daily dose of 200 mg as a secondary prophylaxis, the remaining three patients were treated with intravenous amphotericin B, 50 mg twice a week. After HAART for an average lapse of 16.7 months (10 to 32 months), five cases showed CD4+ cells counts above 150 cells/microl and the remaining 16 presented more than 200 cells/microl; 18 of them had undetectable viral burden and all cases were asymptomatic. The follow up after secondary prophylaxis discontinuation varied between six months and six years (mean= 33.6 months). Twenty out of 21 patients (95 %) were clinically stable, without any manifestation of relapses, including two patients who abandoned HAART. One patient, who discontinued HAART, contracted a fatal bacterial pneumonia. Even though the limited number of cases, the data presented in this study seem to suggest that it is possible to interrupt antifungal secondary prophylaxis of histoplasmosis, when the patient is clinically asymptomatic and the CD4+ cells counts are above 150 cells/microl.

Blockade of endogenous leukotrienes exacerbates pulmonary histoplasmosis

Leukotrienes are classical mediators of inflammatory response. New aspects of leukotriene function have recently been described. We examine here the previously unreported role that leukotrienes play in the regulation of cytokines in a murine model of histoplasmosis. We demonstrate that administration of MK 886, a leukotriene synthesis inhibitor, caused Histoplasma capsulatum-infected mice to die by the day 15 of infection, whereas the correlating death rate in untreated infected mice was 0%. Treating infected animals with MK 886 inhibited leukotriene synthesis but increased leukocyte recruitment to the lungs. Subsequent to this phenomenon, levels of tumor necrosis factor alpha, interleukin-1 (IL-1), IL-6, and KC chemoattractant cytokines and fungi in the lung parenchyma increased, as did inflammatory response. In contrast, IL-2, IL-5, IL-12, and gamma interferon cytokine levels actually decreased. Thus, murine response to pulmonary histoplasmosis may be leukotriene modulated. This finding may enable us to alter the course of the immune response and inflammation caused by histoplasmosis. The data from the present study suggest an important new strategy for immunologic or drug intervention in human patients.

Severe histoplasmosis in travelers to Nicaragua

We investigated an outbreak of unexpectedly severe histoplasmosis among 14 healthy adventure travelers from the United States who visited a bat-infested cave in Nicaragua. Although histoplasmosis has rarely been reported to cause serious illness among travelers, this outbreak demonstrates that cases may be severe among travelers, even young, healthy persons.

Mucosal and Systemic Fungal Infections in Patients with AIDS

In countries where highly active antiretroviral therapy (HAART) is widely available, a decrease in the incidence of fungal infections has been observed in the last 5 years compared with countries that cannot afford this treatment. Even refractory fungal infections may be controlled when HAART is given to patients, and end-stage AIDS infections, such as aspergillosis, are now only infrequently seen. In contrast, fungal infections in certain regions, such as penicilliosis in Southeast Asia or cryptococcosis in Sub-Saharan Africa, are a growing problem. Antifungal therapy for documented infections has not changed very much during recent years; however, new drugs such as caspofungin and voriconazole may be more effective in the treatment of opportunistic fungal infections, in particular, those involving resistant organisms. Secondary antifungal prophylaxis for many opportunistic pathogens can now be temporarily or even permanently discontinued in many HIV-positive patients who have a marked improvement in immune function parameters, such as CD4(+) cell counts, after initiation of HAART. The link between effective virustatic control of HIV infection and a decreasing incidence of fungal infections has been recognised; and so, despite the availability of very effective new antifungal drugs, the cornerstone of treatment and prevention of opportunistic fungal infections in patients with HIV infection is effective antiretroviral therapy including protease inhibitors.