Aug 2026· Journal of Hematology and Allied Sciences· 0 citations· 12 references
TL;DR
Disseminated histoplasmosis should be considered in patients with prolonged unexplained fever, even in the absence of apparent immunodeficiency, and in selected cases, may help avoid invasive procedures such as bone marrow examination.
Abstract
Histoplasmosis is a systemic fungal infection caused by inhalation of spores of
Histoplasma capsulatum
. The disease is endemic in several geographical regions worldwide, including parts of India such as West Bengal, Assam, and selected areas of southern and northern India. Sporadic cases have also been reported from Gujarat and Rajasthan. However, being tropical countries with lots of other infections, histoplasmosis becomes a relatively rare infection and is often missed in routine clinical practice. In patients presenting with pyrexia of unknown origin, delayed diagnosis of disseminated histoplasmosis may result in catastrophic consequences. We report the case of a 29-year-old male, grain merchant by occupation, presented with a fever of 1-month duration. He had previously received empirical broad-spectrum antimicrobial therapy at another hospital without clinical improvement. At presentation, the patient was ill-appearing and hemodynamically unstable. On physical examination, mild splenomegaly was present, and the chest was clear on auscultation. Laboratory evaluation demonstrated bicytopenia, raising suspicion for hematological malignancy or overwhelming systemic infection. Fluorodeoxyglucose (FDG)-positron emission tomography computed tomography demonstrated diffuse marrow hypermetabolism and FDG-avid hepatosplenomegaly, further increasing suspicion for malignancy. Bone marrow aspiration and biopsy were planned, but due to hemodynamic instability could not be performed; however, peripheral blood smear examination revealed intra- and extracellular small oval yeast-like organisms morphologically suggestive of
H. capsulatum
. The patient was treated with an induction therapy dose of Liposomal amphotericin B 3 mg/kg/day for 7 days. Fever subsided within 24 h of therapy, accompanied by rapid clinical and hemodynamic improvement. Following induction therapy, maintenance treatment with oral itraconazole was initiated with a loading dose of 200 mg thrice daily for 3 days, followed by 200 mg twice daily, planned for 1 year. Disseminated histoplasmosis should be considered in patients with prolonged unexplained fever, even in the absence of apparent immunodeficiency. Peripheral blood smear examination may provide an important diagnostic clue and, in selected cases, may help avoid invasive procedures such as bone marrow examination. Early recognition and prompt initiation of antifungal therapy can result in rapid clinical improvement and may be lifesaving.
The importance of recognizing histoplasmosis in high-risk populations and the need for integrated care approaches is emphasized and increased awareness, early clinical suspicion, and access to appropriate diagnostics are essential to improve outcomes.
Cinthya Karina Mejía-Escobar, José Roberto Andino, Sandra Montoya et al.· Journal of the Pediatric Inf...· 0 citations
Histoplasmosis is a fungal infection caused by Histoplasma capsulatum, highly endemic in Central and South America, the United States, and Africa. The fungus exists as a mold in the environment and as yeast in human tissue, proliferating in soils contaminated by bird and bat excrement in environments like caves, abandoned buildings, and construction sites. In immunocompetent hosts, histoplasmosis is often asymptomatic, but in immunocompromised individuals, including pediatric patients, it can lead to disseminated disease with severe outcomes. Misdiagnosis as tuberculosis is common, and incidence rates are underreported. Nonspecific symptoms such as fever, fatigue, hepatosplenomegaly, and hematologic abnormalities complicate diagnosis, and the disease disproportionately affects children under 2 years old or those with compromised cellular immunity.
This study reports four pediatric cases of disseminated histoplasmosis from Hospital Escuela in Honduras. Case 1: A 3-year-old male with interleukin-12 receptor deficiency and a history of Mycobacterium bovis infection developed severe disseminated histoplasmosis and succumbed to multiorgan failure. Case 2: A 3-year-old female from a rural area presented with neuroinfection and hydrocephalus; post-mortem analysis confirmed Histoplasma capsulatum. Case 3: A 14-year-old male with previous histoplasmosis presented with reactivation and responded favorably to itraconazole. Case 4: A 6-year-old male with disseminated tuberculosis and histoplasmosis faced disease related complications resulting in death.
Disseminated histoplasmosis in pediatric patients presents unique challenges, particularly in resource-limited settings, where diagnostic tools such as antigen detection, cultures, and molecular techniques may be unavailable. Increased awareness, early clinical suspicion, and access to appropriate diagnostics are essential to improve outcomes. This study emphasizes the importance of recognizing histoplasmosis in high-risk populations and the need for integrated care approaches.
Cinthya Karina Mejía-Escobar, José Roberto Andino, Sandra Montoya et al.· Journal of the Pediatric Inf...· 0 citations
Histoplasma capsulatum is a dimorphic fungus endemic to the Ohio and Mississippi River valleys that typically causes self-limited pulmonary disease in immunocompetent individuals. Immunocompromised patients, particularly those receiving TNF-α inhibitors, face substantially elevated risk for severe and disseminated infection. Empyema due to histoplasmosis is exceedingly rare, with fewer than five cases documented in the published literature.
We report a 51-year-old woman with rheumatoid arthritis on adalimumab, methotrexate, and hydroxychloroquine who presented with progressive dyspnoea, fever, and hypoxia after multiple prior healthcare encounters. Imaging demonstrated diffuse bilateral micronodules, lingular consolidation, and a worsening left pleural effusion requiring chest tube drainage. Initial urine Blastomyces antigen testing returned positive due to cross-reactivity, but pleural fluid culture and PCR ultimately confirmed Histoplasma capsulatum thus establishing the diagnosis of Histoplasma empyema. Treatment with liposomal amphotericin B followed by itraconazole, combined with pleural drainage, resulted in clinical and radiographic resolution.
This case highlights the diagnostic challenges of Histoplasma empyema, including nonspecific presentation, low pleural fluid culture sensitivity, and antigen cross-reactivity with Blastomyces. A multimodal diagnostic approach and early combined antifungal and drainage-based management are essential for favourable outcomes in immunocompromised patients with atypical or refractory pleural disease.
Vikram Oke, Aditi Iyer, J. Do et al.· Research Connections· 0 citations
Histoplasmosis is a fungal infection caused by Histoplasma capsulatum, which is endemic in several countries, including Brazil. Disseminated histoplasmosis is a severe manifestation caused by the systemic spread of the infection. It usually occurs in immunocompromised patients, particularly in individuals with HIV infection and transplant recipients, but few reports have described cases in immunocompetent individuals. This report describes a case of disseminated histoplasmosis with oral and intestinal manifestations in a non-HIV patient with a history of alcohol abuse, hepatitis B, lymph node, and pulmonary tuberculosis, but no known risk factor for disseminated histoplasmosis. At physical examination, the patient presented with bilateral submandibular lymphadenopathy. A chest radiograph revealed a diffuse micronodular infiltrate with bilateral hilar and right paratracheal lymph node enlargement. Histopathological analysis of oral lesion confirmed the diagnosis of chronic and active ulcerated mucositis associated with a fungal infection suggestive of histoplasmosis. Due to a previous history of intestinal histoplasmosis with incomplete treatment, colonoscopy and intestinal biopsy were performed and confirmed gastrointestinal involvement by disseminated histoplasmosis. Treatment with intravenous amphotericin B followed by itraconazole maintenance therapy resulted in complete regression of the oral lesion and clinical improvement of the gastrointestinal manifestations. This case report contributes to the clinical data on histoplasmosis in non-HIV patients and helps clarify its diagnosis in immunocompetent individuals or those with unclear immunosuppression status.
Débora de Souza Ferreira Sávio, Maria Júlia Pagliarone, J. Faria et al.· SN Comprehensive Clinical Me...· 0 citations
IntroductionMelioidosis is an emerging infectious disease caused by Burkholderia pseudomallei, commonly seen in tropical regions and increasingly reported in India. It presents with a wide spectrum of clinical manifestations and often mimics other infectious or malignantconditions, leading to diagnostic challenges, especially in immunocompromisedindividuals.Case PresentationA 62-year-old male, a known case of non-small cell lung carcinoma post chemoradiotherapy, presented with left upper abdominal pain and intermittent fever for two months to our multispecialty hospital in South India. He had underlying diabetes mellitus. Imaging revealed hepatosplenomegaly with a splenic abscess. Aspiration of the collection showed neutrophilic predominance, and microbiological culture grew Burkholderia pseudomallei. Tuberculosis and malignancy were ruled out. The patient was diagnosed with melioidosis presenting as a splenic abscess without pulmonary involvement. He was treated with intravenous ceftazidime followed by oral cotrimoxazole, along with supportive care and glycemic control.ResultsThe patient showed significant clinical improvement with resolution of fever and stabilization of laboratory parameters. No complications were observed during hospitalization, and he was discharged in stable condition on prolonged eradication therapy.ConclusionThis case highlights an unusual extrapulmonary presentation of melioidosis in an immunocompromised host, emphasizing the importance of early microbiological diagnosis and targeted therapy. A high index of suspicion is essential to avoid misdiagnosis and ensure timely management.
Dr.AnkitaSharma, Dr.NitashaSharma, Dr.RajendraSharma et al.· Asian Journal of Medical Res...· 0 citations
Introduction Acute lymphoblastic leukemia (ALL) is a rare hematologic malignancy that leads to significant qualitative and quantitative lymphocyte deficits. These immunological gaps predispose patients to various bacterial and opportunistic infections. Brucellosis, an intracellular infection endemic in many regions including Iran, presents with nonspecific symptoms such as prolonged fever, malaise, and organomegaly, which closely mimic the clinical manifestations of leukemia. Their co‐occurrence, even in brucellosis‐endemic areas, is actually rare. In addition, their similarity in clinical presentation can result in diagnostic delay or misdiagnosis. Case Presentation A 47‐year‐old male shepherd from an endemic region in Iran presented with a 1‐month history of progressive weight loss, fever (38.4°C), and muscle cramps. Initial physical examination revealed pallor and tachycardia without lymphadenopathy. Laboratory investigations showed severe leukocytosis (103 × 103/μL) and elevated lactate dehydrogenase (1190 U/L). Although initial serological tests for brucellosis (Wright and 2‐ME) were negative, bone marrow aspiration and flow cytometry confirmed B‐cell ALL. Cytogenetic analysis identified the Philadelphia chromosome (t (9; 22), p210 transcript). The patient began induction chemotherapy with the hyper‐CVAD regimen combined with dasatinib. Despite hematological improvement, persistent fever and diaphoresis prompted a re‐evaluation for infectious etiologies. Repeated brucellosis testing yielded strongly positive results (Wright 1/320 and 2‐ME 1/640), suggesting a potential prozone effect in initial tests or recent acquisition. Antibiotic therapy with rifampin and doxycycline was integrated into the oncological protocol. The patient showed rapid clinical improvement within 1 week and subsequently achieved complete remission, which was maintained throughout a 2‐year follow‐up. Conclusion This case highlights the importance of considering brucellosis in the differential diagnosis of febrile patients with hematologic malignancies in endemic areas. Overlapping symptoms can lead to diagnostic delays. It is crucial to repeat serological tests or use serial dilutions to circumvent the prozone effect when clinical suspicion persists in immunocompromised patients.
Parisa Bahramian, M. Ghalamkari, M. Khatuni et al.· Case Reports in Hematology· 0 citations