Complex treatment strategies are necessary to tackle multi-drug resistant tuberculosis (MDR-TB). Adverse drug reactions (ADRs) are well documented but currently there are very few guidelines for drug monitoring aimed specifically at the durations of treatment used in MDR-TB.1Methods
We retrospectively reviewed all MDR-TB patients seen at our Trust over the last 5 years to determine which ADRs were most common and how they are assessed. We examined epidemiological factors (age, sex, ethnicity, and duration in UK), drug regimens, duration of treatment, treatment completion, ADR monitoring, and ADRs reported. All patients had baseline blood tests, visual acuity and Ishihara plates.Results
18 patients were reviewed (12 male) with a mean age of 34.4 (range 10–80) years. One was HIV positive. Thirteen had lived in the UK for <10 years (2>10 years). Three were born in the UK (1 white ethnicity). Treatment regimens included a combination of 4–5 drugs selected from first line oral agents (pyrazinamide or ethambutol), 2nd line oral bacteriostatics (PAS, prothionamide, cycloserine), a fluoroquinolone (moxifloxacin or ofloxacin), drugs which have an unclear role, (clarithromycin) and an aminoglycoside used during the first intensive phase. Planned duration of treatment for all patients was 24 months. Nine completed 2 years, two completed > 2 years, six are on-going and one died. Reported ADRs included nausea and vomiting (38.9%), visual impairment (38.9%), hearing loss (27.8%), tinnitus (27.8%), hypothyroidism (16.7%), arthralgia (16.7%), hepatic impairment (11.1%), renal impairment (5.6%) and also fatigue, headache, rash, pruritis and dizziness. ADRs were detected through a combination of self-reporting of symptoms and direct questioning. Appropriate blood tests and drug levels were taken regularly but not following a recognised protocol.Conclusions
MDR-TB treatment regimens use toxic drugs over long periods. We support the development of a series of systematic evidence-based protocols for assessing ADRs and organisation of monitoring tests in MDR-TB patients which can be used by both physicians and specialist nurses. This should include baseline screening, regular blood tests, audiometry and visual testing as well as drug level monitoring.