Evaluating the prevalence and antibiotics susceptibility profile of Streptococcus pyogenes among patients 5 – 20 years with acute bacterial pharyngitis attending the Limbe Regional Hospital, South West, Cameroon

Background: Streptococcus pyogenes (S. pyogenes) is a gram-positive bacterium which is the leading cause of pharyngitis, skin and soft tissue infection and post streptococcal syndromes. Due to lack of β-lactamase enzyme production, it is considered universally susceptible to penicillin group and later generation of β-lactam antibiotics. As such, empirical treatment is common which might lead to the development of antibiotics resistance. Therefore, determining the prevalence and antibiotics susceptibility of Streptococcus pyogenes acute pharyngitis is really a public health concern in this community.

Objective: This study was aimed at determining the prevalence and antibiotics susceptibility profile among patients 5 – 20 years with acute bacterial pharyngitis at the Limbe. Regional Hospital

Methods: A hospital based cross-sectional study design was used with enrollment of 98 participants aged 5 – 20 years using a convenience sampling technique for a period of one month. A structured questionnaire was used to collect socio-demographic data and risk factors. Streptococcus pyogenes was identified by a throat swab and subsequent culture on 5% sheep blood agar with an overnight incubation at 37°C. A gram stain, catalase and bacitracin test was done to identify S. pyogenes. After identifying the S. pyogenes, an antibiotics sensitivity testing was done to determine the sensitive antibiotics for the S. pyogenes acute pharyngitis. Then the data collected was entered and analyse using SPSS version 28. Finally, stepwise, chi square were carried out for identifying factors having significant association (p<0.05) with acute pharyngitis using SPSS version 20.

Result: A majority of participants where aged 5-9 yrs (41.8%), male: female ratio 1:1 and over 80.6% lived in urban zonws and over half acquired primary education. The prevalence of S. pyogenes was 10.2%. Prevalence was not statistically significant with socio-demographic data (p>0.05). Prevalence with respect to symptoms was found not statistically significant with p>0.05, however more positive cases were observed with pain on swallowing and itchy throat. Some risk factors identified were greatly significant to S. pyogenes acute pharyngitis, which were; malnutrition, passive smoker and number of 1`people that share bed with their P-values 0.003, 0.006 and 0.004 respectively. All isolates were sensitive to penicillin and ampicillin wheras other antibiotics were resistance which were; clindamycin, ceftriaxone, chloramphenicol, tetracycline and erythromycin with percentages 5 (50%), 4 (40%), 2 (20%), 2 (20%) and 1 (10%) respectively.

Conclusion: The prevalence of S. pyogenes was guaged at 10.2% which is considered as low prevalence. Malnutrition, passive smokers and number of bed shared were some risk factors identified with P-values 0.003, 0.006 and 0.004 respectively. All S. pyogenes isolate remain sensitive to penicillin and ampicillin and resistant to clindamycin, ceftriaxone and erythromycin. Continuous surveillance of antibiotics resistance pattern of S. pyogenes for acute pharyngitis must be strengthen to improve the use of antibiotics in hospitals.