Introduction: Streptococcus pneumoniae affects both children and adults worldwide. It colonizes the nasopharynx, and this precedes and serves as a reservoir for invasive disease, for example, pneumonia, bacteremia, and meningitis. It is a leading cause of morbidity and mortality among the elderly and those with underlying medical conditions like immunosuppression and chronic medical illnesses. The increasing number of persons with immunosuppression susceptible to pneumococcal infection has had an impact on the disease burden and the clinical characteristics of the pneumococcal disease in many areas. People with human immunodeficiency virus (HIV) are particularly at risk for persistent infection because of the numerous abnormalities in their immune process like defects in their T cells, B cells, macrophages, and polymorphonuclear cells such as neutrophils. There are limited data on prevalence, outcome, and antimicrobial susceptibility of S. pneumoniae bacteremia among hospitalized patients in Uganda.
Objectives: To determine the prevalence, short-term clinical outcome and antimicrobial susceptibility patterns of S. pneumoniae bacteremia among febrile patients admitted to the emergency medical ward at Mulago hospital.
Methods: Descriptive cross-sectional study with follow-up of patients with confirmed S. pneumoniae bacteremia on blood culture. Febrile patients with an oral temperature of 37.8°C and above were sampled consecutively until the sample size was achieved. Using a standardized questionnaire, data on sociodemographics clinical features and outcome were collected. Blood was drawn for complete blood cell count, serum chemistry, bacterial culture, and sensitivity. Data were analyzed using SPSS version 12.0.
Study Setting: Emergency medical ward, Mulago Hospital Kampala, Uganda. Study participants: a total of 386 febrile patients aged 13 to 81 years, who were admitted from November 2006 to March 2007 in the emergency medical ward were enrolled.
Results: The prevalence of S. pneumoniae bacteremia was 9.8% (38/386). Majority of patients with S. pneumoniae bacteremia were aged between 21 and 35 years. Females were 52.6%. Of these, 68% were HIV infected. The mean oral temperature was 38.6°C. Cough was reported by 78.9% (P = 0.018), and headache by 36.8%, chest signs (P = 0.088), meningeal signs (P = 0.001). Cigarette smoking was noted in 15.8% (P = 0.775). Atadmission, 50% had features of consolidation on chest x-ray, 28.9% (11/38) were multilobar. The mean neutrophil percentage was 77.4 ± 12.6% (P = 0.004), with a neutrophilia of 75% or higher present in 68%, impaired renal function with creatinine level of 1.3 mg/dL or higher was found in 68% (P = 0.001).
All S. pneumoniae bacteremia isolates were resistant to cotrimoxazole, but all were susceptible to ceftriaxone and erythromycin although only 21.1% were susceptible to penicillin. The mean hospital stay was 8.6 days. In the course of hospitalization, 34.2% progressed to have septicemia, 28.9% pneumonia whereas 13.0% developed meningitis while on the ward. Complete recovery was noted in 78.9% and mortality in 7.9% (3/38) because of S. pneumoniae meningitis with HIV coinfection.
Conclusions: S. pneumoniae bacteremia is common among febrile patients admitted on the medical emergency ward at Mulago Hospital. Morbidity is characterized by fever, cough, and headache. The isolates are resistant to cotrimoxazole and penicillin which are the commonly available antibiotics. Mortality is more likely in those with leucopenia, anemia, dehydration, and S. pneumoniae meningitis with HIV co-infection.