In developing countries, newborn omphalitis may contribute significantly to morbidity and mortality. Community-based identification and management of omphalitis will require standardised clinical sign-based definitions. This study aimed to identify optimal sign-based algorithms to define omphalitis in the community and to evaluate the reliability and validity of cord assessments by non-specialist health workers for clinical signs of omphalitis.
Within a trial of the impact of topical antiseptics on umbilical cord infection in rural Nepal, digital images of the umbilical cord were collected. Workers responsible for in-home examinations of the umbilical cord evaluated the images for signs of infection (pus, redness, swelling). Intra- and inter-worker agreement was evaluated, and sensitivity and specificity compared to a physician-generated gold standard ranking was estimated.
Sensitivity and specificity of worker evaluations were high for pus (90%, 96% respectively) and moderate for redness (57%, 95% respectively). Swelling was the least reliably identified sign. Measures of observer agreement were similar to that previously recorded between experts evaluating subjective skin conditions. A composite definition for omphalitis that combined pus and redness without regard to swelling was the most sensitive and specific.
Two sign-based algorithms for defining omphalitis are recommended for use in the community. Focusing on redness extending to the skin around the base of the stump will identify cases of moderate and high severity. Requiring both the presence of pus and redness will result in a definition with very high specificity and moderate to high sensitivity.