Delayed diagnosis of tuberculosis in the state of Maryland and its impact on transmission

Rationale. Anecdotal and published evidence in Maryland have suggested that some TB diagnoses were extremely delayed and may have led to increased transmission. The present study was conducted to determine the extent of delayed diagnosis of TB, to assess patient and provider factors associated with longer delays and to determine if prolonged delays result in increased TB transmission.; Methods and study population. All patients reported to the Maryland Department of Health and Mental Hygiene with a positive culture for Mycobacterium tuberculosis from June 1, 2000 to November 30, 2001 were interviewed; questionnaires ascertained symptom onset and duration, health care visits and potential barriers to health care.; “Patient delay” was defined as the number of days from first TB symptoms to first health care visit for those symptoms. “Health care delay” was defined as the number of days from the first consultation with a medical provider to the initiation of treatment for tuberculosis.; Cox proportional hazards models were constructed to determine demographic, presentation and diagnostic risk factors for delays. Multivariate modeling using generalized estimating equations was used to explore patient factors associated with increased risk of tuberculin skin test (TST) positivity among contacts.; Results. Median patient, health care and total delays were 32, 26 and 89 days, respectively for 158 pulmonary TB patients. Non-White and lower educated patients had longer patient delays, as did foreign-born patients who feared being reported to immigration authorities. Older patients and English speaking patients had increased health care delays, as did patients who received a diagnosis of a respiratory illness and non-tuberculosis antibiotics prior to a TB diagnosis. Only fifty-seven percent of patients initially diagnosed with community-acquired pneumonia received a chest radiograph. When physicians used any TB diagnostic tool (chest radiograph, acid-fast bacilli culture, TST), diagnosis was most often made in a timely fashion. Finally, increased delays resulted in increased TST positivity among patient contacts.; Conclusion. Physicians are underutilizing available diagnostic tools when presented with symptomatic patients, which often leads to non-TB diagnoses and increased diagnostic delays. Physicians in low TB incident areas, especially those in private practice, need to increase their awareness of the current epidemiology of TB and make better use of available diagnostic tools if delays and transmission are to be reduced.