Oli Howlett is a General medicine and Respiratory dual advanced trainee based at Waikato hospital in his final year of training. Originally from the UK and trained at King’s College London, Oli moved to NZ in 2013. With a keen interest in Medical Education Oli has previously been a Clinical Medical Education Fellow for the University of Auckland and is currently an Hon. Clinical Lecturer.
Pulmonary Non-Tuberculous Mycobacterium Infection: The Waikato Experience 2010-2017
Background and Aims: Non-tuberculous mycobacterium (NTM) refers to more than 150 acid fast staining, ubiquitous environmental bacterial species causing a wide spectrum of pulmonary disease. Published New Zealand data is limited. We reviewed the experience of treating NTM at Waikato hospital (a tertiary New Zealand hospital).
Method: A retrospective review of all positive pulmonary NTM cultures between January 2010 and December 2017 from Waikato hospital was undertaken. Epidemiological information (age, sex, ethnicity), sub-species, presence of concurrent microorganism, background respiratory pathology, mortality data were recorded. Samples were considered clinically significant as per BTS/ATS guidelines. Patients were divided into clinically significant, treated and untreated and clinically insignificant groups. Data on treatment regimen, duration, outcome, reason for treatment failure were recorded. Comparisons including BMI and functional status were recorded between the treated and untreated groups as well as mortality data.
Results: 240 patients were identified (46% male), 65% NZ European, 13% Maori (Maori form 23% Waikato population). 137 had clinically insignificant isolates. 68 had a clinically significant isolate, were reviewed and a decision was made not to treat. 35 patients received treatment (mean age 70, 71% female), of which 69% had bronchiectasis. 31% achieved culture conversion. 69% failed treatment. Reasons for failure include, 29% had refractory disease, 25% GI upset, 17% died on treatment, 8% had LFT impairment, 8% rash and 4% QTc prolongation. Of the 11 patients successfully treated no patient has died. There was a statistically significant difference in performance scores between the treated and untreated groups.
Conclusion: This is the first comprehensive review of NTM pulmonary disease treatment in New Zealand. Waikato outcomes are suboptimal compared to current published international literature, however the reasons for this are complex. Performance status scoring as be indicated as a useful method of predicting who may fail treatment in our experience.