Case Report

A Rare Case of Disseminated Histoplasmosis in anImmunocompetent Young Male: Diagnostic Value of Bone MarrowBiopsy and Fungal Morphological Identification

Muhammad Shayan Ashfaq
Aga Khan University Karachi, Pakistan
Natasha Ali
Aga Khan University Karachi, Pakistan

✉ Correspondence: Muhammad Shayan Ashfaq Email: shayanthebest911@gmail.com

DOI https://doi.org/10.70302/jpsim.v7i2.2632
Volume: 7, Issue 2 Pages: 160–162 Published: 03 Jun 2026
Received: 04 Nov 2025 Revised: 14 Apr 2026 Accepted: 04 May 2026 Published Online: 03 Jun 2026

Abstract

The dimorphic fungus Histoplasma capsulatum causes histoplasmosis, an infection that can manifest as anything from a simple, self-limiting illness to a serious, widely spread illness. Fungal culture is still the gold standard for confirmation, but diagnosis is sometimes delayed by its slow development. Bone marrow analysis can offer a quick and accurate diagnostic substitute in these situations. We describe a male immunocompetent patient, age 21, who has had a persistent fever and malaise for three months that have not improved with empirical treatment. Repeated blood cultures and serologic testing came out negative, but laboratory studies showed cytopenias. Grocott-Gomori methenamine silver and periodic acid-Schiff stains, on the other hand, revealed intracellular and extracellular yeast-like organisms in bone marrow aspirate and trephine biopsy that were morphologically consistent with Histoplasma capsulatum.

Keywords
Histoplasma capsulatum disseminated histoplasmosis bone marrow biopsy cytopenia fungal morphology

How to Cite This Article

Ashfaq MS, Ali N. A Rare Case of Disseminated Histoplasmosis in anImmunocompetent Young Male: Diagnostic Value of Bone MarrowBiopsy and Fungal Morphological Identification. J Pak Soc Intern Med. 2026;7(2):160–162. doi:10.70302/jpsim.v7i2.2632

Conflict of Interest

All authors declare no competing interests.

Disclosed in accordance with ICMJE and COPE guidelines.

Funding

No specific funding was received for this research.

Funder information follows the Crossref Funder Registry standard.

References

  1. Kauffman CA. Histoplasmosis: a clinical and laboratory update. Clin Microbiol Rev. 2007;20(1):115-32.
  2. Wheat LJ, Azar MM, Bahr NC, Spec A, Relich RF, Hage C. Histoplasmosis. Infect Dis Clin North Am. 2016;30(1):207-27.
  3. de Perio MA, Benedict K, Williams SL, Niemeier-Walsh C, Green BJ, Coffey C, et al. Occupational Histoplasmosis: Epidemiology and Prevention Measures. J Fungi (Basel). 2021;7(7):510.
  4. Hage CA, Azar MM, Bahr N, Loyd J, Wheat LJ. Histoplasmosis: Up-to-Date Evidence-Based Approach to Diagnosis and Management. Semin Respir Crit Care Med. 2015;36(5):729-45.
  5. Shaikh MS, Majeed Memon A. Disseminated histoplasmosis in an immuno-competent young male: Role of bone marrow examination in rapid diagnosis. Diagn Cytopathol. 2018;46(3):273-6.
  6. Adenis AA, Aznar C, Couppié P. Histoplasmosis in HIV-Infected Patients: A Review of New Developments and Remaining Gaps. Curr Trop Med Rep. 2014;1(2):119-28.
  7. Soeroso NN, Aida A, Pratiwi WB, Utama BSP, Syahruddin E, Sembiring RE. Chronic pulmonary histoplasmosis masquerading as tuberculoma: A case report and literature review. Int J Surg Case Rep. 2025;133(1):111555.
  8. Azar MM, Hage CA. Laboratory Diagnostics for Histoplasmosis. J Clin Microbiol. 2017;55(6):1612-20.
  9. Agarwal P, Capoor MR, Singh M, Gupta A, Chhakchhuak A, Debatta P. An Unusual Presentation of Disseminated Histoplasmosis: Case Report and Review of Pediatric Immunocompetent Patients from India. Mycopathologia. 2015;180(5-6):359-64.
  10. Bardia PC, Detroja KN, Maniar RC, Dharsandia HK. A case of disseminated histoplasmosis diagnosed by bone marrow aspiration in immunocompetent patient from nonendemic area, Rajkot, Gujarat. Indian J Pathol Microbiol. 2024;67(1):230-2.
  11. Smith DJ, Soebono H, Parajuli N, Grijsen ML, Cavanaugh AM, Chiller T, et al. South-East Asia regional neglected tropical disease framework: improving control of mycetoma, chromoblastomycosis, and sporotrichosis. Lancet Reg Health Southeast Asia. 2025;35:100561.
  12. Naji A, Baxter M, Kumi A, Camille Ozaeta J, Onuoha N, Cruz-Vasquez D, et al. A fungal nightmare: A rare and deadly presentation of disseminated histoplasmosis. ID Cases. 2024;38:e02084.

Reference list indexed for Google Scholar and ResearchGate. DOI links resolve via doi.org.

CC BY CC BY 4.0 This article is published under the Creative Commons Attribution 4.0 International License. May be shared and adapted with attribution. © 2026 Journal of Pakistan Society of Internal Medicine.
📃 In This Issue View All
Original Article Outcomes of Laparoscopic Cholecystectomy in Acute Cholecystitis: A Retrospective Analysis Raza SH, Butt N, Qureshi AM Original Article Comparison of Ultrasound-Guided versus Landmark-Based Central Venous Catheter Insertion Zafar S, Gillani SA Original Article Neonatal Sepsis: Bacteriological Profile and Antibiogram in a Tertiary Care Hospital Iqbal M, Rashid T Original Article Serum Ferritin as a Prognostic Marker in COVID-19 Severity: A Hospital-Based Study Rehman N, Sheikh I, Javed K Original Article Impact of Diabetes Mellitus on Post-Operative Wound Healing in General Surgery Siddiqui FA, Noor M, Akhtar W
👥 More by These Authors
Review Article Thyroid Disorders in Pregnancy: Clinical Implications and Management Strategies Baig BI, Usman A Original Article Prevalence of Hypertension Among Urban Adults in Pakistan: A Cross-Sectional Study Khan TM, Ahmed S, Malik RA Review Article Antibiotic Resistance Patterns in Community-Acquired Pneumonia: Emerging Trends Hussain I, Farooq Z Review Article Statin Therapy in Non-Alcoholic Fatty Liver Disease: A Systematic Review Nawaz F, Cheema HA, Mehmood Y
🔗 Related Articles By Keywords
Original Article Neonatal Sepsis: Bacteriological Profile and Antibiogram in a Tertiary Care Hospital Iqbal M, Rashid T Original Article Serum Ferritin as a Prognostic Marker in COVID-19 Severity: A Hospital-Based Study Rehman N, Sheikh I, Javed K Original Article Impact of Diabetes Mellitus on Post-Operative Wound Healing in General Surgery Siddiqui FA, Noor M, Akhtar W Original Article Cervical Cancer Screening Awareness Among Rural Women in Punjab Bibi S, Anjum R, Hassan F