Leishmaniasis - Still a diagnostic challenge: An individual participant data systematic review.

Leishmania, endemic in nearly half the world's countries, continues to pose significant diagnostic challenges. Our systematic review sought to analyse problems in diagnosis especially in low- to middle-income countries. The average time from symptom onset to diagnosis was 4.5 years. While microscopic detection often failed, polymerase chain reaction showed high sensitivity. Clinical presentations varied significantly, highlighting the complexity of diagnosing leishmaniasis, especially in patients with prolonged disease in non-endemic areas.