Management of Pneumocystis jirovecii Pneumonia

Diagnosis

The Centers for Disease Control and Prevention recommends that diagnosis should be established before initiating treatment, though empiric therapy may be started if clinical suspicion is high while awaiting results 1
Fiberoptic bronchoscopy with bronchoalveolar lavage (BAL) is the preferred diagnostic method with 87-95% sensitivity, as recommended by the Centers for Disease Control and Prevention 1
Positive quantitative PCR (>1450 copies/ml) for P. jirovecii from BAL should trigger treatment initiation, according to the European Society for Medical Oncology 2
The Centers for Disease Control and Prevention recommends that transbronchial biopsy is not recommended unless BAL is negative or nondiagnostic 1
Open-lung biopsy, while most sensitive, is not routinely recommended due to invasiveness, as stated by the Centers for Disease Control and Prevention 1

The Centers for Disease Control and Prevention recommends TMP-SMX as the first-line treatment for documented PCP, with a dosage of 75-100 mg/kg/day of SMX and 15-20 mg/kg/day of TMP divided every 6 hours for 14-21 days 1, 2
After acute pneumonitis resolves, patients with mild to moderate disease without malabsorption may complete the 21-day course with oral therapy at the same dose, as recommended by the Centers for Disease Control and Prevention 1

The Centers for Disease Control and Prevention recommends pentamidine isethionate 4 mg/kg/day IV once daily over 60-90 minutes for patients intolerant of TMP-SMX or with clinical treatment failure after 5-7 days 1
Clindamycin plus primaquine is the preferred alternative for TMP-SMX-intolerant patients, according to the European Society for Medical Oncology 2

For non-HIV patients with critical respiratory insufficiency due to PCP, adjunctive glucocorticosteroids are not generally recommended, as stated by the European Society for Medical Oncology 2

Patients who have been successfully treated for PCP should receive secondary prophylaxis to prevent recurrence, as recommended by the European Society for Medical Oncology and the American College of Rheumatology 2, 3
Options for secondary prophylaxis include TMP-SMX one double-strength tablet daily, as recommended by the Centers for Disease Control and Prevention 4

Prophylaxis is indicated for HIV-infected patients with CD4+ T-cell counts <200 cells/μL, as recommended by the Centers for Disease Control and Prevention 5
For non-HIV immunocompromised patients on triple immunosuppressive therapy, prophylaxis with TMP-SMX is recommended, according to the European Society of Medical Oncology and the American Society of Hematology 6

Solid organ or hematopoietic stem cell transplantation confers the highest risk for PCP within the first six months after transplant. 7

About 10 % of patients have sulfonamide hypersensitivity, requiring the use of alternative treatment agents. 7

Outbreaks in Australian transplant units have shown patient‑to‑patient airborne transmission of PCP, highlighting the importance of rigorous infection‑control measures. 7