INTRODUCTION:Pneumocystis jiroveci Pneumonia (PJP) is an opportunistic infection associated with significant morbidity and mortality. Cushing’s syndrome (CS) with very high cortisol levels can cause an immunocompromised state which predisposes such individuals to many opportunistic infections including PJP. We describe a case of PJP in a patient who was recently diagnosed with Cushing’s syndrome.
CASE PRESENTATION:A 52 year old female presented to the Emergency Room with altered mental status and respiratory difficulty. She recently had been diagnosed with CS in Guatemala and the extent of work-up was unknown. The family denied any symptoms of fever, cough, emesis, abdominal or urinary symptoms. Examination revealed a tachycardic, tachypneic and confused patient. Oxygen saturations were in the low 80s on room air. Other significant findings were hyperpigmentation, moon facies, dry mucous membranes, abdominal striae, decreased breath sounds at the lung bases and symmetric decreased strength with no focal neurologic deficit. Admission labs were significant for hypokalemia, hypomagnesemia and hypoxia on arterial blood gas analysis. She was intubated for worsening hypoxia and mental status. CXR revealed moderate infiltrate in the left lower lobe. She was empirically treated for community acquired pneumonia. A bronchoscopy on the day of admission revealed friable and erythematous mucosa. Bronchoalveolar fluid came back negative for routine cultures, AFB and fungal stains and urine legionella antigen was negative. Her clinical condition and CXR continued to worsen for the next 48 hours. PJP was suspected at this point given her high cortisol level. A tracheal aspirate came back positive for Pneumocystis jiroveci by direct fluorescent antibody test. HIV test was negative. Patient responded well to trimethoprim/sulfamethoxazole and other antibiotics were stopped. She was later discharged home in a stable condition. Work up of her CS revealed a serum cortisol of 101 mcg/dL, ACTH of 44 pg/ml, 24 hour urine cortisol of 2853 mEq, CT of the head demonstrated an empty sella turcica and an octreotide scan revealed moderately increased uptake in the left hepatic lobe consistent with somatostatin receptor positive tumor.
DISCUSSIONS:PJP in association with Cushing’s syndrome (CS) is rare with only a handful of cases described in the literature. While the clinical presentation of PJP is usually more indolent and slowly progressing in the HIV positive patients, it can be of abrupt onset with rapid decline in non-HIV patients as in this case. The incidence of opportunistic infections in CS is approximately 11-17% (1). The risk of such infections may be particularly increased once cortisol-lowering therapy is initiated (1). However in our case the PJP occurred before initiation of treatment for CS. Patients with CS are unable to localize infections well either on radiographic images or by clinical and laboratory parameters, which in turn often leads to a significant delay in diagnosis and initiation of therapy. As a result, morbidity and mortality are increased. The degree of cortisol elevation is correlated with clinical outcome, with higher levels associated with multiple opportunistic pathogens and increased mortality (2). In addition to PJP many other opportunistic infections have been described in CS including Aspergillus, Candida, Herpes Simplex, Nocardia and Cryptococcus (2).
CONCLUSION:Pneumocystis carinii pneumonia should be considered in the differential diagnosis of pneumonia in patients with Cushing’s syndrome. Primary prophylaxis for PJP should be started simultaneous with cortisol-lowering therapy. Furthermore, in the setting of otherwise unexplained opportunistic infection, Cushing’s syndrome should be considered in the differential diagnosis.
DISCLOSURE:Raghu Reddy, None.