Pneumocystis carinii pneumonia (PCP)—now referred to as Pneumocystis jirovecii!

We recently had a case of ?PJP...

Here is a quick review!

PJP is commonly associated with HIV-positive patients, in particular, those with a low CD4 count. Interestingly, patients with normal immune function may be colonized, but asymptomatic; these individuals may serve as a reservoir for the future spread of PJP to immune-compromised patients. This condition occurs more commonly in patients that are immune-compromised, but keep these risk factors in mind:

•  Infections: i.e. HIV
• Glucocorticoid use or other immunosuppressive or cytotoxic medications (i.e. chemotherapy)
• Malignancy (especially hematological forms)
•  Primary immune deficiencies (i.e. severe combined immunodeficiency)
• Hematopoietic stem cell or solid organ transplantation
• Agents used to treat certain rheumatological conditions

Clinical presentation: may present with fever and dry cough. The presentation is generally more severe in non-HIV patients compared to those that are HIV-positive

HIV-positive patients: may present with gradual and indolent onset of symptoms, including a cough (usually non-productive), fever, progressive dyspnea, fatigue, chills. Some patients describe weight loss and chest pain.

Imaging

CXR: variable patterns, including

• Diffuse, bilateral interstitial infiltrates
•  Nodules (solitary or multiple), some may become cavitary
•  Cystic appearance

CT Thorax: extensive ground glass opacities, cystic lesions

Diagnosis
-Rapid: analysis of induced sputum (by inhalation of hypertonic saline)

·      If negative, and you have a high index of suspicion—proceed to bronchoscopy with bronchoalveolar lavage (BAL)

-PCR assays: to detect Pneumocystis in BAL fluid or induced sputum, blood or NP aspirates

Treatment- in HIV-negative patients:

·      TMP-SMX (Septra)- first line

·      Atovaquone 750 mg PO BID (if patients cannot tolerate Septra)

·      Pentamidine IV (if severe infection and patient cannot tolerate Septra)

·      Clindamyin + Primaquine

·      TMP + Dapsone

Duration of therapy: 14-21 days

Treatment in HIV-positive patients:

·      TMP-SMX (320/1600 mg): 2 DS tabs q8h

·      TMP-dapsone

·      Clindamycin-primaquine

·      Pentamidine

Duration of therapy: 21 days

Adjunct: in severe disease, also give corticosteroids as it has been shown to improve outcome without increasing further opportunistic infections