Development and evaluation of an egg hatching technique for diagnosis of schistosomiasis mansoni

The modified quantitative Kato-Katz fecal smears are considered by the WHO as the golden technique for diagnosing intestinal schistosomiasis. The sensitivity of the Kato-Katz smears decreases when tile intensity of infection is low. Some modified hatching techniques when compared with the Kato-Katz thick smears revealed a higher sensitivity. The present work aims at developing and evaluating an egg hatching test to be used for diagnosis of schistosomiasis mansoni under field conditions. Stool samples were collected from 284 human cases from five different Egyptian governorates. Only samples confirmed positive for S. mansoni infection in our laboratory by the Kato-Katz fecal thick smears or the modified hatching technique were considered positive and used in the present work. A portion of each stool sample was examined by three Kato-Katz thick smears. Another portion [3 gm] was examined by the developed hatching technique. Diagnosis based on three Kato-Katz thick smears revealed a sensitivity of 94.7%. The hatching technique detected 85.2% of the cases during the first day examination, but after two days examination it detected all tile cases, i.e. 100% sensitivity. Results showed that the highest daily sensitivity of the hatching technique was during the first day [85.2%], followed by a gradual decrease of the daily sensitivity to 65.8% in the second, 14.4% in the third, and zero in the fourth and fifth days. Diagnosis based on the hatching technique used in the present study is significantly more sensitive than three Kato-Katz thick smears. The modified hatching technique is simple and can be easily used under field conditions

study on a cercarial assay for detection of praziquantel-resistance in Alexandria [Egypt]

Praziquantel [PZQ] has been used extensively and successfully in national schistosomiasis control programs in Egypt and there are reports of emerging PZQ resistance. The aim of this work was to use an in vitro assay for detection of PZQ resistance in Egyptian field and laboratory strains of Schistosoma mansoni cercariae. The assay was performed on ordinary glass slides. Cercariae were exposed to a final concentration of 0.5x10[-7] M or 5x10[-6] M PZQ. They were examined and counted at 0, 20, 40 and 60 minutes. In some samples the assay was coupled with scanning electron microscopy to detect any PZQ-induced tegumental changes in cercariae. After exposure to 5x 10[-7] M or 5x 10[-6] M of PZQ, there was a gradual decrease in the proportion of unaffected cercariae. The effect of the exposure time on the percentage of unaffected cercariae of the laboratory and field strains was significant in the two concentrations of PZQ. The low concentration of the drug did not succeed to cause significant differences between the two isolates of cercariae throughout a 60-minute exposure time. Surprisingly, the high concentration of PZQ showed a significant difference in the response of the two isolates where the field strain was more affected after exposure to PZQ for 60 minutes. The results of the SEM showed that all cercariae exposed to PZQ for 30 or 60 minutes were influenced, as blebs appeared in the body tegument, unlike the unexposed cercariae. The in vitro assay results indicated that PZQ resistance may not constitute a real problem in the field isolates of S. mansoni cercariae in Alexandria. However, why the field isolates showed significantly higher susceptibility to PZQ needs further investigations

Tachycardia induced dilated cardiomyopathy in pediatric patients

To study the diagnosis and treatment of tachycardia induced dilated cardiomyopathy in infants and children with unexplained systolic dysfunction. The present study was conducted on 22 patients were regularly attending the arrhythmology clinic section of pediatric cardiology unit at Cairo University Hospital suffering from significant arrhythmias induced heart failure that determined clinically and by investigations. All cases were subjected to the following; full medical history taken, thorough clinical examination, chest and heart x-ray, 12 leads ECG, 24 hours electrocardiographic recording [Holter monitoring] and standard echocardiographic evaluation included real time two-dimensional echocardiogram, M-mode and Doppler measurement. All studied cases with tachycardia induced DCM underwent medical treatment of arrhythmia with remission of the DCM. Studied cases showed good response to medical treatment in the form of anti-arrhythmic drugs [amiodarone alone [12] or in combination with sotalol [8] / lanoxin [1] or verapamil [1]] where sinus rhythm with normalization of ventricular function was achieved in treated cases. The manifestations of heart failure were eliminated clinically [via return of heart rate and respiratory rate to normal values for age] and radiologicaly. Holter monitoring was done only for 19 cases and showed return to sinus rhythm with normal heart rate for age [<0.001 highly significant] and improvement of echocardiographic variables [LVEDD, LVESD, EF and Fractional shortening for age]. One child continued to have frequent episodes of tachycardia and underwent successful AV nodal ablation with permanent pacemaker implantation. Two out of the 22 patients on amiodarone could be managed with only digoxin and verapamil after their ventricular function had returned to normal. Tachycardia induced cardiomyopathy is a reversible form of dilated cardiomyopathy and heart failure, where its diagnosis requires high index of suspicion. Medical treatment with amiodarone and/or B-blockers is a safe and effective treatment strategy for infants and children with tachicardiomyopathy. This approach may avoid unnecessary ablations in children or at least postpone it till the procedure would be safer

Efficacy of praziquantel against Giardia lamblia in rats: parasitological, pathological and therapeutic study

Four-five weeks old rats were included in this study and divided into two experimental groups received single or split doses of praziquantel [PZQ] as well as two control groups, one infected untreated and the other normal healthy rats. The effect of infection on rat growth as well as the jejunal and duodenal architecture was histopathologically studied after H and E staining. The jejunal ultrastructure was examined by SEM and TEM. The effect of PZQ was evaluated using the same techniques. It was observed that infected as well as infected treated animals had less weight than the healthy controls. The intensity of infection decreased gradually after treatment. The cure rate was 100% after split dose and 80% after a single dose. Altered villus height and cryptic depth were the characteristic changes in the architecture of the duodenum and jejunum, more pronounced in the latter. The split dose of PZQ revealed a more improvement of the histopathological findings than the single dose. By SEM, circular imprints representing defects in the villi were observed in the jejunum. By TEM deformation of microvillar architecture was observed together with organellar changes in the RER and the mitochondria after PZQ treatment

comparative study on the effect of praziquantel and triclabendzole on vampirolepis nana in vitro

V. Nana was frequently associated with Schistosoma mansoni and Fasciola spp. This study was conducted to investigate and compare the effects of praziquantel and triclabendazole on V. nana worms after in vitro exposure to 1 and 2 mug/ml of each of praziquantel or triclabendazole. All the worms were put under observation for 30 minutes. The worm mortality rates were recorded and the topographic tegumental changes were studied by scanning electron microscopy. The results demonstrated that praziquantel showed comparatively superior effect on adult V. nana worms than triclabendazole. The latter still revealed an anthelmintic effect