Clinical complexities in diagnosing and managing leptospirosis in New Zealand: a qualitative analysis

Leptospirosis is a bacterial zoonosis often under-diagnosed due to its presentation as an undifferentiated febrile illness. This study aimed to explore the clinical complexities involved in diagnosing and managing leptospirosis cases in New Zealand.

Qualitative content analysis of clinical notes from 42 leptospirosis cases used a dual deductive and inductive approach to identify key themes.

Three key themes emerged, highlighting the critical role of clinician reasoning in early detection and appropriate clinical response: 1) multiple factors contribute to delayed diagnosis, including incomplete exposure histories and deviation of symptoms from textbook definitions, 2) there were challenges with diagnosis and the use of medication in post-acute care, and 3) interpretation and use of confirmatory tests was inconsistent and complex. Clinicians were confident in suspecting leptospirosis when clinical history taking also assessed relevant exposure.

Based on these findings, we have made recommendations to prevent delayed diagnosis. We advocate updating clinical references to better reflect New Zealand-specific disease presentation and risk factors to support early diagnosis. National standardisation of diagnostic test timing, selection and interpretation is recommended, alongside clearer notification pathways. Further research could focus on early diagnostic markers to improve clinical decision making in practice.