Nasopharyngeal carriage rate of Streptococcus pneumoniae in Ugandan children with sickle cell disease

Abstract

BackgroundNasopharyngeal carriage of Streptococcus pneumoniae is a determinant for invasive pneumococcal disease, which often complicates homozygous sickle cell disease. Here, we determined the nasopharyngeal carriage rate of S. pneumoniae in Ugandan children with homozygous sickle cell disease, who attended the outpatient Sickle Cell Clinic at Mulago National Referral hospital in Kampala, Uganda.ResultsS. pneumoniae occurred in 27 of the 81 children with homozygous sickle cell disease (giving a carriage rate of 33%, 27/81). Twenty three children were previously hospitalized of whom S. pneumoniae occurred in only two (9%, 2/23), while among the 58 who were not previously hospitalized it occurred in 25 (43%, 25/58, χ2 = 8.8, p = 0.003), meaning there is an association between high carriage rate and no hospitalization. Two children previously immunized with the pneumococcal conjugate vaccine did not carry the organism. Prior antimicrobial usage was reported in 53 children (65%, 53/81). There was high resistance of pneumococci to penicillin (100%, 27/27) and trimethoprime-sulfamethoxazole (97%, 26/27), but low resistance to other antimicrobials. Of the 70 children without sickle cell disease, S. pneumoniae occurred in 38 (54%, 38/70) of whom 43 were males and 27 females (53% males, 23/43, and 56% females, 15/27).ConclusionNasopharyngeal carriage of penicillin resistant pneumococci in Ugandan children with homozygous sickle cell disease is high. While nasopharyngeal carriage of S. pneumoniae is a determinant for invasive pneumococcal disease, pneumococcal bacteremia is reportedly low in Ugandan children with sickle cell disease. Studies on the contribution of high carriage rates to invasive pneumococcal disease in these children will be helpful. This is the first report on pneumococcal carriage rate in Ugandan children with sickle cell disease.

Relationship between antibiotic resistance and sickle cell anemia: preliminary evidence from a pediatric carriage study in Ghana

“…S. pneumoniae carriage among subjects with HbSS disease in the current study (10%) is similar to a carriage rate of 16% previously reported among HbSS disease children in Ghana,6 but significantly lower than most of the carriage rates (>40%) that have been reported generally among children in Ghana 28,29. The relatively lower carriage rate of S. pneumoniae among pediatric subjects with HbSS disease in Ghana, which has also been reported in Uganda7 and in some western countries such as the USA,20 is probably due to the routine prophylactic use of penicillin among people with HbSS disease. Contrary to the disparity of S. pneumoniae carriage between people with and without HbSS disease in Ghana (as described above), we did not observe a relatively lower carriage rate of S. aureus among people with HbSS disease, probably because unlike S. pneumoniae , S. aureus is highly resistant to penicillin because of its production of beta-lactamase 21…”

“…Carriage rates of S. pneumoniae among children with HbSS disease reported in other countries were 33% in Uganda,7 14% in Gabon,8 13% in the USA,26 and 21% in the UK 27. S. pneumoniae carriage among subjects with HbSS disease in the current study (10%) is similar to a carriage rate of 16% previously reported among HbSS disease children in Ghana,6 but significantly lower than most of the carriage rates (>40%) that have been reported generally among children in Ghana 28,29.…”

“…However, the study did not include a control arm, which makes it difficult to deduce any trend in antibiotic resistance that may be peculiar to people with HbSS disease. Recently, a Ugandan study showed that S. pneumoniae carried by people with HbSS disease were highly resistant to penicillin and cotrimoxazole, compared to a control group, but no significant variations were observed for chloramphenicol, erythromycin, cefriaxone, rifampin, or perfloxacin 7. Carriage studies that have investigated antibiotic resistance among people with HbSS disease in sub-Saharan Africa seem to have focused on S. pneumoniae ,6–8 which is probably due to the prominence of the organism in bacteraemia in HbSS disease in Africa.…”

Carriage of Streptococcus pneumoniae and Other Respiratory Bacterial Pathogens in Low and Lower-Middle Income Countries: A Systematic Review and Meta-Analysis

“…In Kenya, the prevalence of carriage in HIV-infected children 3–59 months of age was higher than in those uninfected (76% [95% CI, 66%–84%] vs. 65.8% [95% CI, 64.0%–67.5%], p = 0.04) [52], [58]. One study, from a low income country (Uganda), reported a 33% prevalence in children aged 8 months–6 years with homozygote sickle cell disease, a prevalence which was lower than in HIV-infected children in the same age category [59].…”

Prevalence and Aetiology of Bacteremia in Febrile Children With Sickle Cell Disease at a Nigerian Tertiary Hospital

“…A study in Tanzania also revealed a predominance of Staphylococcus aureus and rarity of Streptococcus pneumoniae 21. Reasons that have been attributed to the low incidence of Pneumococcal infections in some African countries include greater difficulty in isolating fastidious organisms like Pneumococcus compared with organisms like Staphylococcus aureus and the possibility of unregulated antibiotic usage in these countries 9,22. It is possible that use of antibiotics purchased across the counter for febrile illnesses eliminate some organisms including Pneumococci such that affected children rarely present in hospital.…”