The approach to the diagnosis of P. carinii pneumonia and its treatment remain controversial. Some advocate the use of clinical criteria alone in the diagnosis of P. carinii , however it has become increasingly clear that such an empiric regimen may be associated with an overall worse outcome for the patient.
Diagnostic testing requires obtaining an adequate respiratory sample.
The necessary steps for using sputum as a screening tool probably include a specific protocol for obtaining the sample and the use of more sensitive stains such as fluorescent markers or PCR to detect the microorganism. On the other hand, BAL is used to diagnose pneumonia due to P. carinii or other microorganisms.