Assessing the Effectiveness of Empiric Aantibiotic Treatments: The Use of an Antibiogram Based Methodology in the Case of Selected Public Hospitals in Lesotho

Antibiotics prescribed in the presumptuous treatment of infections may be ineffective if causative pathogens acquire resistance to prescribed antibiotics. In the absence of patient follow ups for treatment outcome assessments, healthcare providers may be unaware of the effectiveness of antibiotic treatments they provide. In the empiric treatment of infections particularly, such situations may compromise appropriate selection of antibiotics. The study aimed at assessing the effectiveness of antibiotics prescribed in the empiric treatment of infections using a methodology based on information derived from antibiograms. Culture sensitivity test results and relevant data on antibiotic treatment among inpatients from selected hospitals were used to construct an antibiogram and also determine pathogen associations with infections and antibiotics most frequently prescribed in their empiric treatment. Parameters describing levels of antibiotic activities against pathogens associated with given infections were defined and used to evaluate the effectiveness of prescribed antibiotics. Clinical validity of results was assessed by comparing results of a simultaneous treatment outcome evaluation of antibiotic treatments of selected infections carried out. The methodology was used to successfully evaluate the effectiveness of commonly prescribed antibiotics. Ampicillin and co-trimoxazole, two of the antibiotics most prescribed in the empiric treatment of infections, were predicted to be grossly ineffective in treating staphylococcal and Gram-negative bacilli (GNB) infections for which they were observed to be prescribed. Polymicrobial causes of infections attributable mainly to gram-positive cocci and gram-negative bacilli were established as an etiological feature of most infections. Multiple antibiotic treatments were shown, in effect, to be more effective than single use of the agents in treating most infections.