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Cutaneous Pneumocystis Jirovecii Infection in an Allogeneic Stem Cell Transplant Recipient
Nikhil Sood1, Aniket Vadnerkar2, Murali Kodali3
1Department of Medicine, Banner Health, Gilbert, USA.
Abstract:
Pneumocystis jirovecii is an opportunistic fungus that infects the lungs but can involve other organs, including the skin and lymph nodes. Risk factors include human immunodeficiency virus (HIV), solid organ/haematological malignancies and a CD4 cell count of fewer than 200 cells/μl. Pneumocystis jirovecii pneumonia (PJP) infection is reported less frequently these days with the advent of prophylaxis with trimethoprim-sulfamethoxazole (TMP-SMX). We report a case of extrapulmonary PJP infection in a patient while receiving pentamidine prophylaxis in a T-cell prolymphocytic leukaemia, who underwent an allogeneic stem cell transplant. There are plenty of reported cases of PJP on pentamidine prophylaxis; however, none had cutaneous PJP infection. Cutaneous P. jirovecii infection (CPJ) is an extrapulmonary infection that is rarely reported. Our patient's skin biopsy was inconclusive, but the skin nodules improved once he was initiated on TMP-SMX. Many transplant patients cannot tolerate TMP-SMX for various reasons and are placed on second-line prophylaxis for PJP, which does not prevent extrapulmonary PJP infections. Our case highlights the challenges of diagnosing such a rare infection in immunocompromised patients. Extrapulmonary PJP should be suspected in patients with a history of pulmonary PJP and persistent elevated Fungitell® levels in low CD4 counts.
Learning Points:
Extrapulmonary Pneumocystis jirovecii pneumonia (PJP) infection can happen while receiving pentamidine prophylaxis.It is extremely rare to see a cutaneous infection, and no case has been reported in the last two decades.Trimethoprim-sulfamethoxazole (TMP-SMX) remains the first-line treatment for pulmonary and extrapulmonary PJP.
Insights
Extrapulmonary Pneumocystis jirovecii pneumonia (PJP) can occur even with pentamidine prophylaxis. This case highlights a rare cutaneous PJP infection, emphasizing the need for vigilance in immunocompromised patients.
Area of Science:
- Medical Mycology
- Infectious Diseases
- Immunocompromised Hosts
Background:
- Pneumocystis jirovecii is an opportunistic fungus causing pneumonia and extrapulmonary infections.
- Risk factors include HIV, malignancies, and low CD4 counts (<200 cells/μl).
- Prophylaxis with trimethoprim-sulfamethoxazole (TMP-SMX) has reduced PJP incidence.
Purpose of the Study:
- To report an extremely rare case of cutaneous Pneumocystis jirovecii infection (CPJ).
- To highlight diagnostic challenges of extrapulmonary PJP in immunocompromised patients on prophylaxis.
- To underscore the limitations of second-line PJP prophylaxis.
Main Methods:
- Case report of a patient with T-cell prolymphocytic leukaemia undergoing allogeneic stem cell transplant.
- Patient received pentamidine prophylaxis for PJP.
- Diagnosis involved skin biopsy and clinical response to TMP-SMX.
Main Results:
- The patient developed extrapulmonary PJP with cutaneous involvement while on pentamidine prophylaxis.
- Skin biopsy was inconclusive, but nodules resolved with TMP-SMX treatment.
- This represents a rare instance of CPJ, with no similar cases reported in two decades.
Conclusions:
- Extrapulmonary PJP, including rare cutaneous forms, can occur despite pentamidine prophylaxis.
- TMP-SMX remains the gold standard treatment for both pulmonary and extrapulmonary PJP.
- Elevated Fungitell levels and a history of PJP warrant suspicion for extrapulmonary disease in immunocompromised patients.
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