Relevance Of Blood Culture To The Diagnosis And Treatment Of Septicemia

A study of septicaemia was conducted in Enugu metropolis with a view to determine the relevance of blood culture to the diagnosis and treatment of this disease. The subjects comprised of Six hundred and fifty (650) children and adults of both sexes aged between one day to 70 years having clinical features suggestive of septicaemia, who were on admission at University Of Nigeria Teaching Hospitals (UNTH), Enugu.  Their blood specimens were seeded into thioglycolateand glucose broths and incubated at 37 °C for 7 days. Subcultures were performed after 1, 2, 3, 4 and 7 days respectively. Growth (positivity) in the broths was assessed using conventional diagnostic methods namely macroscopy(visualization), Gram filming (microscopy) and culture. The bacterial isolates harvested were subjected to in-vitroantibiotic susceptibility tests using the disc diffusion method. Etiology was established in 104 out of 350 subjects indicating an incidence of 29.7%.

This difference in prevalence among different age groups was statistically significant(P < 0.01). The males (59/350, 16.86%) appeared to be more susceptible to septicaemia than the females (45/350, 12.9%) in all the age groups.

This variation had no statistical significance (P > 0.01). Monomicrobialsepticaemia had ahigher prevalence (91.3%) than polymicrobialsepticaemia (8.65%). Staphylococcus aureusand Escherichia coliconstituted 33.3%. Most of the offensive microbes were facultative anaerobes (93.3%) while very few were strict aerobes (7.69%) and strict anaerobes (1.92%). The isolated anaerobes were Peptostreptococcussp. (1%) and Bacteroidesfragilis(1%). The in vitro susceptibility of the bacterial isolates to antibiotics indicated 78.9-92.9% sensitivity to vancomycin, zinnat, peflacin and fortum. However, they were 60 – 90% resistant to penicillin, ampicillin, tetracycline and septrin. This study confirmed the diverse nature of bacterial etiologies of septicaemia in Enugu metropolis; the need for the use ofthioglycolate broths, first subcultures on or before 24 h instead of starting off for after 48 h of incubation, complementary application of macroscopy, Gram filming and culture including antibiotic susceptibility test as an integral part of diagnosis and treatment of septicaemia is hereby advocated, most especially in the developing countries of the world.