A Unique Case of Pneumocystis Jirovecii (PCP) Pneumonia in HIVUninfected, COVID -19 Positive Patient

ABSTRACT

INTRODUCTION: Covid- 19 has been associated with various fungal infections in immunocompetent/immunocompromised patients. We report the second case of PCP pneumonia coinfection in a HIV- uninfected man with COVID-19. CASE A 52 y/o man with PMH of hyperlipidemia, gout, viral myocarditis and no prior immunodeficient conditions was admitted to hospital for COVID-19 SARS (Severe Acute Respiratory Syndrome) CoV- 2 Pneumonia. He was initially treated with Dexamethasone 6mg/day, Remdesivir and Tocilizumab x 2doses and oxygen therapy. On day 4, he was transferred to ICU for acute hypoxemic respiratory failure requiring NIV eventually requiring intubation with Fio2-60-90%. His course was complicated by AKI, septic shock requiring pressor for BP support. He received empiric ceftriaxone and Hydrocortisone for suspected adrenal insufficiency. Despite antibiotics, labs showed increasing WBC count with decreasing procalcitonin. Blood/urine cultures no growth. Tracheal cultures Ceftriaxone-sensitive E.coli therefore was continued on ceftriaxone. On ICU day3, he was still febrile so was started on prophylactic Bactrim for PCP suspecting immunosuppression although he was never treated with long term high dose steroids. Fungal cultures, Aspergillus, HIV, Beta-D glucan - negative. He was afebrile after 7days of antibiotics and PCP testing was done to discontinue Bactrim. Tracheal aspirate culture reported positive for PCP diagnosed with IFA stain. LDH - 471 but is an unreliable marker in the setting of covid pneumonia. HRCT was not attained due to unstable hemodynamics. Prophylactic Bactrim was then switched to therapeutic dose and also started on Prednisone 40mg twice daily on tapered dose. DISCUSSION: PCP is an infection commonly seen in immunocompromised individuals but may colonize healthy individuals remaining asymptomatic and serving as a reservoir to transmit and affect immunocompromised hosts with immunodeficiency syndromes/malignancy/organ transplant. Diagnosis is made via identification of organism via staining/PCR. Based on previous case series reported by Mayo Clinic amongst HIV- uninfected individuals, an average dose of steroids was 30mg/ day (minimum-16mg/ day) for an average duration of 12 weeks (minimum-8weeks) to acquire PCP infection. Our subject was treated with Hydrocortisone dose equivalent to a prednisone dose ∼ 75mg/day x 1 week which may have induced immunosuppression or due to COVID-19 infection itself making him susceptible for PCP infection. First case of PCP pneumonia coinfection in COVID-19 (recovered) was reported in March 2021. CONCLUSION: Our case report is unique for two reasons, PCP diagnosis via tracheal aspirate and two, detected in COVID-19 infected patient post prophylaxis. PCP coinfection with COVID-19 should be identified and treated.