Molecular diagnostic techniques overcome some of the deficiencies of blood culture by their rapidity, sensitivity and specificity 17. Squire et al 16 in a post-mortem study obtained negative blood cultures in 18 per cent of infants who died of bacterial infection. Schelonka et al 15 reported that in infants with low numbers of bacteria, as much as 60 per cent of culture results may be false negative with blood culture volumes of 0.5 ml. However, the negative results could merely be due to an incomplete course of treatment resulting in the persistence of the bacteria in the blood. Yet another cause for negative blood culture could be the treatment with antibiotics prior to sample collection. Empirical antibiotic treatment is resorted to due to additional concerns such as the intermittent release of organisms in some clinical situations leading to negative results in blood culture. However, there is a justified concern regarding the ability to recover bacteria from the small volume of blood and often, this prompts the clinicians to treat with antibiotics despite a negative blood culture 14. In spite of the low sensitivity, blood culture has not been replaced by any other technique since isolation of the bacteria is essential for performing antibiogram 13. Presently blood culture is considered the gold standard for the diagnosis of neonatal sepsis although new proteomics-based and genomics-based rapid diagnoses have been developed 3, 12. and Gram positive bacteria such as Staphylococcus aureus and Group B Streptococcus 7, 8, 9, 10, 11. The source of infection may be vertical being prenatally acquired from the mother or horizontally transmitted from the nosocomial environment 6 with the most common agents being Gram negative bacteria such as coliforms ( Escherichia coli, Klebsiella spp., Enterobacter spp.), Pseudomonas spp., Acinetobacter spp. The bacteriological profile of the causative agent varies between developed and developing countries 5. The clinical signs and symptoms are very subtle and variable and hence cause difficulty in diagnosis 4. ![]() Neonatal sepsis is the most common cause of neonatal death 2 and, therefore, early diagnosis 3 and treatment is very important. Neonatal septicaemia is a leading cause of morbidity but also in mortality of infants not only in the developing but also in developed countries and is responsible for 30-50 per cent deaths in developing countries 1.
0 Comments
Leave a Reply. |
Details
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |