Estimation of total IgE, blood eosinophils and phagocytic activity in human scabies


Background: Scabies is a contagious disease. It can be easily misdiagnosed with many other dermatological conditions.
Objective: This study was designed to evaluate some laboratory methods, (e.g. IgE,NBT) which might be useful in confirming the diagnosis of scabies, and to follow up the response of the patients after treatment.
Patients and method: This study was conducted on 103 patients from Al- Zenjelli Custody (jail) in Mosul City (Iraq) over a period of 6 months (Oct. 2001 to April 2002). Blood samples from 103 scabietic patients and 40 control subjects were analysed by using various tests including total white blood cell count, eosinophil count and nitroblue tetrazolium (NBT) positive neutrophils count. Plasma total IgE levels were measured for only 70 patients and 20 control subjects by using Enzyme Linked Immunosorbent Assay (ELISA).
Results: Plasma total IgE level showed a significant raise in patients with scabies in comparison to control group. (p< 0.05)The NBT test revealed a significant raise in both treated and non-treated subjects in comparison to control group. (p<0.05) Also, the untreated patients showed a higher NBT positive neutrophils than the treated ones. Eosinophil counts were higher in patients with scabies than the control subjects in the first few postinfection days. (p<0.001) Total white blood cell counts revealed no significant variation between patients and control groups.
Conclusion: The results indicate that nitroblue tetrazolium (NBT) test was the best in comparison to other tests. It was used to study the role of phagocytosis in scabies. Its increase reflected an efficient innate immunity. This test might explain to us some immunopathological aspects of this disease and its symptoms which might help in diagnosis and follow up of patients with scabies.

Key words: Scabies, IgE, NBT


Scabies, IgE, NBT