Histoplasma capsulatum: An Unusual Case of Pericardial Effusion and Coarctation of the Aorta

Histoplasmosis Causing Overt Inflammation Presenting as Pericarditis: A Case Report

Histoplasma capsulatum is a well-known cause of pulmonary infections, but in the right patient population or host environment, it can cause a vast array of symptoms. The fungus possesses a special set of virulence factors that allows it to evade host immunity and cause infection, particularly in immunosuppressed hosts. Pericarditis is a known presentation of histoplasmosis, but it can be difficult to diagnose and is often treated based on suspicion. We present a case of a healthy young male who mounted a robust inflammatory response to histoplasmosis resulting in pericarditis.

Pericardial effusion in an immunocompetent host- a unique presentation of histoplasmosis

Histoplasma capsulatum infection is infrequently considered in the differential diagnoses for acute pericarditis in immunocompetent hosts when presenting with tamponade physiology, given its gradual infective nature. We describe a case of a young male presenting solely with acute pericarditis with pericardial effusion and early cardiac tamponade physiology secondary to a pulmonary histoplasmosis infection. Our patient had no pulmonary symptoms; the only pulmonary manifestation of histoplasmosis included incidental findings of subcarinal lymphadenopathy and a left lingular nodule abutting the pericardium. Given failure of symptom improvement with pericardiocentesis and first-line therapy for idiopathic/viral pericarditis, further workup of the pulmonary nodule was pursued. Histopathologic analysis of tissue showed caseating granulomas and fungal Grocott-Gömöri's methenamine silver stain revealed yeast consistent with Histoplasma species. The patient improved with itraconazole therapy.

Learning objective

Pulmonary histoplasmosis has potential to present as a pericardial effusion in the immunocompetent individual. In addition to pericardiocentesis, antifungal therapy can be curative.

Can urinary histoplasma antigen test improve the diagnosis of histoplasmosis in a tuberculosis endemic region?

BACKGROUND

Many patients with histoplasmosis are treated with anti-tubercular therapy (ATT) in tuberculosis endemic regions as diagnosis of histoplasmosis requires invasive sampling. We sought to study the utility of urinary Histoplasma antigen detection test.

METHODS

Case records of patients with a diagnosis of histoplasmosis prior to (Period A) and after (Period B) introduction of urinary Histoplasma antigen detection test were analysed in this single centre retrospective study.

RESULTS

Thirty-seven patients (18 in Period A, and 19 patients in Period B) were studied. There was nearly a threefold increase in diagnoses (from 0.39 cases to 1.18 cases per month) after the introduction of antigen test. Nine patients (24.3%) were immunocompromised (6 had HIV infection and 3 were on steroids), and 28 (75.6%) were immunocompetent. Empirical ATT had been given to 10 patients prior to histoplasmosis diagnosis. Invasive tissue sampling was required in only two patients in Period B to confirm the diagnosis. Immunocompromised patients were younger, were more likely to have skin and mucosal findings, anaemia and leucopenia as compared to immune-competent patients.

CONCLUSION

This study emphasises that histoplasmosis cases may be missed and patients may receive ATT unnecessarily. Histoplasma antigen increased the diagnostic yield by almost threefold in our study.

Fulminant Cryptococcus neoformans infection with fatal pericardial tamponade in a patient with chronic myelomonocytic leukaemia who was treated with ruxolitinib: Case report and review of fungal pericarditis

Cryptococcus neoformans is a saprophytic fungal pathogen that can cause serious illness in immune-compromised hosts and it presents with a wide variety of clinical symptoms. We present a fatal case of fulminant C. neoformans infection presenting as pericardial tamponade in a 71-year-old male with chronic myelomonocytic leukaemia undergoing chemotherapy with the JAK-STAT inhibitor ruxolitinib. We also review the published cases of fungal pericarditis/tamponade. In addition to illustrating an atypical presentation of C. neoformans, this case highlights the risk for opportunistic fungal infections in patients with haematological malignancies, especially the ones treated with small molecule kinase inhibitors.