Tuberculosis diagnosed during pregnancy: a prospective study from London

A study was undertaken to characterise the presentation of tuberculosis in pregnancy and the difficulties in diagnosis in an area of the UK with a high incidence of tuberculosis.

A prospective case series was investigated at Northwick Park Hospital, a university affiliated district general hospital in Brent and Harrow health authority in north-west London which incorporates a regional infectious diseases unit. Patients diagnosed with tuberculosis over the study period were included if the onset of symptoms occurred during pregnancy.

Thirteen patients were diagnosed during a 30 month period from December 1995 to May 1998 during which 9069 mothers were delivered, a prevalence of 143.3/100 000 deliveries. Symptoms began at a median of 22 weeks gestation (range 9-40 weeks). All patients were recent immigrants of Indian subcontinent or Somali origin and their median duration of residence in the UK was 31 months (range 1-72). Prevalence broken down for racial origin of mothers was 466.3/100 000 for mothers of black African origin and 239.1/100 000 for mothers of Indian origin. Nine of the 13 patients had extrapulmonary tuberculosis. Four patients with widely disseminated disease had a negative Mantoux response and five with localised disease had a strongly positive Mantoux response. HIV co-infection was absent. The median delay between the onset of symptoms and diagnosis was seven weeks (range 2-30). The response to standard treatment was excellent and all patients were cured.

Tuberculosis occurring in pregnancy is common in recent immigrants. Diagnosis during pregnancy is delayed because the disease is frequently extrapulmonary with few symptoms.