The gold standard for diagnosing pneumocystis jirovecii pneumonia is by isolating the bug itself either by DFA or culture. This task is much harder in non-HIV patients as the organism load is much lower. This meta-analysis examined 14 studies, most were retrospective. 2 only included patients with HIV, 8 with both HIV and non-HIV patients with other types of immunosuppression, and 2 with non-HIV immunosuppressed patients.
Using this pool of studies, the authors found that Fungitell had excellent sensitivity 95%, very good specificity 86%, and AUC of 97%.
In cases where obtaining microbiologic samples is impossible, dangerous, or even too difficult – BD glucans may be a way to empirically treat patients with some confidence.