Utility of specific IgG4 response in saliva and serum samples for the diagnosis and follow up of human neurocysticercosis.

This study was aimed to analyze the Ig subtypes and IgG1 and IgG4 subclass responses to crude soluble extract (CSE) antigen and Ag B of Cysticercus cellulosae in pre and post treatment (PT) saliva and serum samples for the diagnosis and follow-up of neurocysticercosis (NCC) patients. Saliva and serum samples collected from 55 patients (15 highly suggestive of NCC clinically and radiologically, 10 hydatidosis, 10 other helminthic infections, 10 tubercular meningitis, 10 neurological disorders other than NCC), 15 normal healthy subjects and 10 NCC patients at 1, 3 and 6 months following albendazole therapy were analyzed for specific IgG, IgG1, IgG4, IgM and IgA antibody responses by ELISA. With the use of CSE Ag, the rank orders in saliva for sensitivity was IgG (71.4%) > IgG1 (68.2%) > IgG4 (65.2%) > IgM (57.7%) > IgA (55.5%) and specificity IgG1 = IgA (93.2%) > IgG = IgG4 = IgM (91.6%) while in serum, sensitivity was IgG (78.9%) > IgG1 (71.4%) > IgG4 (68.2%) > IgA (65.2%) > IgM (62.5%) and specificity IgG1 = IgG4 (90.2%) > IgA (85.9%) > IgG (83.3%) > IgM (82.1%). With the use of Ag B in saliva, the sensitivity was IgG (65.2%) > IgG1 = IgG4 (62.5%) > IgM = IgA (55.5%) and specificity with the use of saliva was IgG1 = IgG4 = IgM (94.8%) > IgG (93.2%) > IgA (91.6%) while with serum the sensitivity was IgG = IgG1 (68.2%) > IgG4 (65.2%) > IgA (62.5%) > IgM (57.7%) and specificity was IgG1 (93.2%) > IgG4 = IgM (91.6%) > IgA (90.2%) > IgG (87.3%). Comparative analysis of antibody responses in patients with single Vs multiple CT scan lesions indicated higher sensitivity in multiple lesion patients. Antibody responses in PT samples indicated that the undetectable IgG4, IgM and IgA responses in saliva samples correlated well with the CT scan reports while in serum samples, responses persisted longer. In conclusion, this study indicated that due to the lower sensitivity of IgM and IgA responses in pretreatment samples, detection of IgG4 subclass in saliva to either CSE Ag or AgB may serve better marker in the NCC follow-up.

Comparative evaluation of hexokinase isoenzyme typing and antigen detection for differentiation of Entamoeba histolytica and Entamoeba dispar.

Entamoeba histolytica, the causative organism of invasive amebiasis is a potential pathogen, while asymptomatic infection is caused by E. dispar. Differentiation of the species is not possible on the basis of morphological characters by microscopic examination. In the present study an attempt has been made to differentiate E. histolytica from E. dispar in 45 isolates obtained from culture and direct stool samples respectively on the basis of hexokinase isoenzyme analysis and Tech Lab ELISA. A 100% correlation was found between these two techniques. However, Tech Lab E. histolytica antigen detection test was found to be both rapid and technically simple. Its use in diagnosis and epidemiological studies is recommended.

Intestinal parasites and intra familial incidence in a low socio-economic area of Chandigarh (North India).

A total of 550 stool samples were collected from a low socio economic population of Chandigarh (North India) and examined macroscopically and microscopically, to determine the prevalence of intestinal parasitic infections and their familial incidence. The overall prevalence rate was 19.3%. Ascaris lumbricoides and Giardia lamblia were the commonest, affecting 51 (9.3%) and 33 (6.0%), respectively. In 17 (22.7%) families the same parasite was observed to infect multiple family members, which included A.lumbricoides (in 9 families), G. lamblia (in 7 families) and H. nana (in 1 family). The results of present study indicate that there is a high prevalence of parasitic infection in the community where personal hygiene and sanitary conditions are poor and may be one of the contributing factors for transmission within the families. Intervention strategies including health education program should be designed and implemented to control parasitic infections.