Serum 25-hydroxy vitamin D in surface and underground coalminers.

Several antibiotics, including streptomycin, interfere with neuromuscular transmission.2 Neuromuscular blockade usually develops after introduction of the drug into the peritoneal or pleural cavity during operation or after parenteral administration and leads to respiratory difficulties in the immediate postoperative period. Myopathy, however, has not previously been recorded with antituberculous drugs. This case shows that this complication may occur with rifampicin. Thrombocytopenia, acute haemolytic anaemia, the "flu" syndrome, and acute renal failure have all been associated with rifampicin. These side effects are usually seen with intermittent treatment3 or after early reintroduction of rifampicin after completion of a course.4 Renal failure may occur after a treatment gap of more than two years.5 Rifampicin antibodies are more commonly detected in patients who develop side effects, but titres fall at the end of treatment. The rapid onset of myopathy in our patient when rifampicin was reintroduced, compared with the slow development initially, together with a previous uneventful course of treatment suggest a similar mechanism. The proximal myopathy in this patient was directly related to the rifampicin treatment, and this important adverse effect should therefore be considered in any patient who complains of undue weakness during antituberculous chemotherapy.