Recurrent pneumococcal bacteremia: risk factors and outcomes

Recurrent pneumococcal bacteremia receives infrequent mention in the literature, usually in association with patients who are immunocompromised.

To examine recurrent cases of pneumococcal bacteremia to determine risk factors and outcomes (mortality rates and emergence of resistance) associated with recurrences.

We retrospectively reviewed all cases of pneumococcal bacteremia identified by our microbiology laboratory from January 1, 1992, through December 31, 1996. Demographic, clinical, and laboratory data were abstracted.

There were 462 bacteremic episodes in 432 patients; 23 of these patients had 30 recurrent episodes. The 5.3% recurrence rate (23/432) is greater than that previously described. The median time to recurrence was 200 days. The mean age of patients with recurrences was 34 years, 70% were women, all were black or Hispanic (in near equal numbers), and 87% were infected with the human immunodeficiency virus (HIV). Human immunodeficiency virus infection, coexistent cancer, and female sex were independent predictors of recurrence. Only patients who were HIV-infected had multiple recurrences. Isolates from recurrent bacteremias were more likely to be penicillin-resistant than were initial bacteremic isolates (relative risk, 2.0; P =.16). Patients with recurrences had a higher (although not statistically significant) mortality rate than those without recurrences (22% vs 16%; P =.33). There was an inverse relationship between severity of illness and likelihood of recurrence.

Rates of recurrent pneumococcal bacteremia may be higher than previously reported. In patients with recurrent pneumococcal bacteremia, the presence of an underlying immunodeficiency should be investigated.