Performance of loop-mediated isothermal amplification (LAMP) for detection of Schistosoma mansoni infection compared with Kato-Katz and real-time PCR.

The performance of loop-mediated isothermal amplification (LAMP) for detection of Schistosoma mansoni DNA from stool and urine samples in comparison with Kato-Katz and real-time polymerase chain reaction (PCR) was studied. After obtaining informed consent, 50 children participated in the present study and agreed to submit stool and urine samples. Stool samples were examined by Kato-Katz. Both real-time PCR and LAMP techniques were applied on stool and urine samples. The overall prevalence of S. mansoni was 46% in stool and urine samples as detected by the employed techniques, and 90% of cases had light infection intensity. The highest percentage of infection was diagnosed by real-time PCR (44%), followed by Kato-Katz (42%) and LAMP in the stool (36%), while the lowest percentages of infection were diagnosed by real-time PCR and LAMP in urine samples (24% and 14%, respectively). Kato-Katz, real-time PCR and LAMP showed 100% specificity where the sensitivity was 91.3%, 95.7% and 78.3%, respectively, in stool samples. Real-time PCR and LAMP showed lower sensitivity in urine samples. The LAMP assay is a promising technique for S. mansoni diagnosis in endemic countries of moderate and high-intensity infection. Yet, it needs further optimization, particularly in urine samples.

Evaluation of two doses of triclabendazole in treatment of patients with combined schistosomiasis and fascioliasis.

To determine the safety and efficacy of 2 consecutive doses of triclabendazole (TCBZ) in the treatment of Schistosoma mansoni infection in human cases infected with both S. mansoni and Fasciola sp., we conducted a field survey involving 6314 individuals from 15 villages. The overall prevalence of schistosomiasis alone was 15.8%, of fascioliasis alone 2.2%, and of combined infection 0.7%. Treatment with 2 doses of TCBZ was given to the 49 cases with combined infection. Eight weeks after treatment, the cure rate was 96% for fascioliasis and was 32.7% for schistosomiasis. All schistosomiasis cases cured had a low intensity infection. Liver function tests done before treatment and 8 weeks after substantiate the safety of 2 doses of TCBZ given to those with combined infection. Administration of TCBZ should precede praziquantel in treatment of combined infection, however TCBZ cannot be recommended for infection with S. mansoni alone.

Evaluation of two doses of triclabendazole in treatment of patients with combined schistosomiasis and fascioliasis

To determine the safety and efficacy of 2 consecutive doses of triclabendazole [TCBZ] in the treatment of Schistosoma mansoni infection in human cases infected with both S. mansoni and Fasdola spv we conducted afield survey involving 6314 individuals from 15 villages. The overall prevalence of schistosomiasis alone was 15.8%, of fascioliasis alone 2.2%, and of combined infection 0.7%. Treatment with 2 doses of TCBZ was given to the 49 cases with combined infection. Eight weeks after treatment, the cure rate was 96% for fascioliasis and was 32.7% for schistosorniasis. All schistosomiasis cases cured had a low intensity infection. Liver function tests done before I treatment and 8 weeks after substantiate the safety of 2 doses of TCBZ given to those with combined infection. Administration of TCBZ should precede praziquantel in treatment of combined infection, however TCBZ cannot be recommended for infection with S. mansoni alone

Ineffectiveness of myrrh-derivative Mirazid against schistosomiasis and fascioliasis in humans.

The present study assessed the schistosomicidal and fasciolicidal actions of the myrrh-derivative Mirazid in an area of low schistosomiasis transmission. A total of 27 patients infected with Schistosoma mansoni and 16 with Fasciola spp. received the maximum recommended dose of Mirazid. Pretreatment egg counts in 4 Kato-Katz slides were compared with similar counts in stool samples collected 1 and 2 months after treatment. Standard procedures and quality control measures were followed. The results revealed that Mirazid used as schistosomicidal or fasciolicidal agent in the maximum recommended dose has a low cure rate and produced a negligible reduction in egg counts. Prescribing such an ineffective drug in Egypt might endanger the achievements of the schistosomiasis control strategy.

Ineffectiveness of myrrh-derivative Mirazid against schistosomiasis and fascioliasis in humans

The present study assessed the schistosomicidal and fasciolicidal actions of the myrrh-derivative Mirazid in an area of low schistosomiasis transmission. A total of 27 patients infected with Schistosoma mansoni and 16 with Fasciola spp. received the maximum recommended dose of Mirazid. Pretreatment egg counts in 4 Kato-Katz slides were compared with similar counts in stool samples collected 1 and 2 months after treatment. Standard procedures and quality control measures were followed. The results revealed that Mirazid used as schistosomicidal or fasciolicidal agent in the maximum recommended dose has a low cure rate and produced a negligible reduction in egg counts. Prescribing such an ineffective drug in Egypt might endanger the achievements of the schistosomiasis control strategy

Epidemiological, clinical and prognostic profile of acute bacterial meningitis among children in Alexandria, Egypt.

PURPOSE: To address the epidemiological characteristics and clinical indices that may predict the prognostic profile of meningitis among children. METHODS: Children admitted to Alexandria fever hospital with clinical diagnosis of meningitis/meningoencephalitis during the period 2002-2003 were recruited for the study. They were subjected to clinical examination as well as CSF bacteriological and serological investigations. RESULTS: Three hundred and ten patients (195 males and 115 females) were included. About 65.2% of them were infected with acute bacterial meningitis (ABM) and 34.8% were infected with aseptic meningitis. In this study, ABM was caused by Haemophilus influenzae (21%), Streptococcus pneumoniae (13.9%), Neisseria meningitidis (14.2%) and other undetermined bacteria (16.1%). ABM showed significant association with age group 1-9 years (66.3%), low socio-economic class (96%), working mother (83.2%), more than two smokers in the family (62.9%) and cold seasons (fall 35.1% and winter 48.5%). Aseptic meningitis showed significant association with age group 3-15 months (100%) and previous immunization (81.5%). The overall case fatality rate was 10.3%; 13.9% for ABM and 3.4% for aseptic meningitis. 7.1% of all survivors developed epileptic attacks. Predictors for death or epilepsy events were high WHO meningitis score (>or=9), decreased CSF glucose level (<10 mg/dL), more smokers in the family, generalised seizures, infancy (<1 year of age) and working mothers. CONCLUSION: This study highlights the importance of several predictors of the outcome of meningitis in children. It is concluded that quick and simple scoring scales, such as the WHO scale, are not only applicable but valuable prognostic tools for meningitis in children.

Identification of the Egyptian species of Fasciola.

Reports on the species of Fasciola present in the Nile Delta, Egypt, appear controversial. Some authors reported the presence of both Fasciola gigantica and Fasciola hepatica, others reported F. gigantica only and mentioned that F. hepatica was found only in imported animals. This study was an attempt to identify the species of Fasciola flukes collected from locally bred animals. Morphologic, morphoanatomic, morphometric, and chemotaxonomic criteria of the fluke isolates were studied. Speciation based on morphologic and morphometric data was not decisive due to overlap in the values of most measurements. Morphoanatomic data proved the presence of both the species, and isoelectric focusing (IEF) of fluke soluble protein confirmed the presence of both F. gigantica and F. hepatica in Egypt.

Intra-specimen and day-to-day variations of Fasciola egg counts in human stools.

Intra-specimen and day-to-day variations of Fasciola egg counts in stools were investigated for 16 cases of established fascioliasis. For each case six Kato slides from a single stool sample were examined daily for 5 consecutive days. The results indicated the presence of significant intra-specimen variations in more than one-third of the examined series, while the inter-specimen variation was almost negligible. The sensitivity of the Kato-Katz test for diagnosing Fasciola infection with three Kato slides from the same specimen or on different days ranged from 96.0%-99.1%. The examination of three Kato smears from a single stool specimen, which is more feasible in field studies, would give an accurate diagnosis of fascioliasis. Used as such, the Kato-Katz technique is highly sensitive in the diagnosis of fascioliasis.

Intra-specimen and day-to-day variations of Fasciola egg counts in human stools

Intra-specimen and day-to-day variations of Fasciola egg counts in stools were investigated for 16 cases of established fascioliasis. For each case six Kato slides from a single stool sample were examined daily for 5 consecutive days. The results indicated the presence of significant intra-specimen variations in more than one-third of the examined series, while the inter-specimen variation was almost negligible. The sensitivity of the Kato-Katz test for diagnosing Fasciola infection with three Kato slides from the same specimen or on different days ranged from 96.0%-99.1%. The examination of three Kato smears from a single stool specimen, which is more feasible in field studies, would give an accurate diagnosis of fascioliasis. Used as such, the Kato-Katz technique is highly sensitive in the diagnosis of fascioliasis

Specific IgG avidity in acute and chronic human fascioliasis.

The detection of IgG avidity in sera is potentially useful in the diagnosis of acute and chronic infection. We studied IgG avidity in 31 patients with fascioliasis, with the aim of evaluating the clinical application of this test to confirm the diagnosis of incubating cases and to distinguish between acute and chronic cases. Of the 31 cases, 13 were incubating and had a mean avidity index of 57.28 +/- 5.79%. The 18 chronic cases had an avidity index of 68.80 +/- 8.92%. The difference was highly significant. We conclude that IgG avidity is a reliable means of identifying the stage of fascioliasis and suggest a cut-off point of 59.90% to distinguish between acute and chronic infection.

Detection of circulating E/S antigens in the sera of patients with fascioliasis by IELISA: a tool of serodiagnosis and assessment of cure.

An IELISA was developed to evaluate the performance of Fasciola E/S antigens in diagnosis and cure assessment of human Fasciola infection. Twenty patients with acute (prepatent) fascioliasis and another 20 with patent infection were enrolled in the study. Patients were treated with TCZ and followed at 1, 3 and 6 months after therapy. At inspection, the sensitivity of the test to diagnose prepatent cases was 100% compared to 70% for patent infections. There was a gradual decrease of antigenaemia over the follow-up period in acute cases. In chronic cases antigen disappeared from 13 cases (65%) at 1 month; this proportion did not change at 3 or 6 months.

Circulating antibodies and antigens correlate with egg counts in human fascioliasis.

We explored the relationships between specific IgG antibody levels and circulating E/S antigen to intensity of Fasciola infection in the human host. Twenty patients with patent infection and six healthy individuals were enrolled in the study. Intensity of infection was determined by repeated egg counts in stools, while IgG antibodies against adult Fasciola gigantica somatic FI, FII and against E/S antigens were measured as ELISA O.D. readings. The level of circulating E/S antigens was determined by IELISA. Positivity as well as levels of antibodies and antigen correlated with infection intensity. These findings may disclose in the future a relation between morbidity in the acute phase and worm load.

Triclabendazole in the treatment of established human fascioliasis

The tolerance and efficacy of triclabendazole CGP 23030, specially prepared for human use, were assessed in 50 patients in the chronic phase of fascioliasis. After clinical examination, investigation and ultrasonography of the liver and biliary system, triclabendazole 10 mg/kg, either as a single or split dose, was administered. The clinical picture was studied daily for six days and the investigations were repeated 6, 30 and 60 days after treatment. The drug was tolerated. Its side-effects, which included upper abdominal pain, mild fever and limited derangement of liver function, were considered negligible. The cure rate at 2 months was 94% when assessed by the disappearance of eggs in stools and 88% when assessed by both the absence of eggs in stools and of worms in the biliary system. The use of triclabendazole for the treatment of human fascioliasis was found to be justified

Metacercarial precipitin test for diagnosis of human fascioliasis.

A metacercarial precipitin test was devised for diagnosis of human fascioliasis. The sera tested were those of cases of fascioliasis (acute and chronic), of schistosomiasis and of normal healthy individuals. Metacercariae were prepared in the laboratory from naturally infected snails. Serum dilutions of 1:5 (20%) and 1:10 (10%) were incubated with metacercariae for periods of 6, 24 and 48 hours. No precipitation was observed when the sera of healthy persons were used. With sera of fascioliasis cases a precipitate was formed which increased in amount with time. It was more rapid in its formation and greater in its quantity with sera of acute fascioliasis. When incubation was prolonged a free precipitate was seen in the medium. With sera of schistosoma cases, a precipitate was observed in a few cases only; it was negligible in amount and localized to the plug area. Metacercarial precipitin is considered a simple, sensitive and specific test for diagnosis of human fascioliasis. It is recommended to use the serum in a dilution of 1:5 (20%), to give preliminary results after 6 hours incubation and to confirm 24 hours later.

Phagocytic activity of neutrophils in human fasciolosis before and after treatment.

Neutrophil phagocytic function was studied in fifteen patients with chronic fasciolosis and five in the incubating phase of the disease. Results were compared with a control group. The chematactic index which is the ratio of directed to non directed migration, the (NBT) reduction test which estimates phagocytosis and the more recent and specific test the chemiluminescence which measures phagocytosis and intracellular killing were performed. The results showed that in fasciolosis chemotactic activity, NBT and chemiluminescence index were significantly increased as compared to controls. This increase was more prominent in the acute phase. In this stage, the immature parasites are in close contact with the liver tissue. With chronicity of infection, they reach the bile ducts and inflammation in the liver parenchyma subsides. At this stage a lower level of metabolites and antigens reach the tissues, while the majority pass with bile to the intestinal lumen. The indices returned to normal level after treatment of fasciolosis. This signifies disappearance of all stimuli responsible for activation of PMN phagocytes.

Evaluation of Fasciola excretory-secretory (E/S) product in diagnosis of acute human fasciolosis by IgM ELISA.

Diagnosis of fasciolosis in the acute phase depends on a sensitive and accurate serological test. The present study is an evaluation of the efficacy of excretory-secretory Fasciola gigantica adult worm antigen by IgM ELISA. Thirty eight patients with acute fasciolosis and 14 in the chronic phase together with 23 patients with different parasitic infections were introduced in the study. Seventeen healthy, parasite free individuals, were served as controls. A crude excretory-secretory antigen and its fractions I and II (obtained by gel filtration chromatography on Sephadex G-200) were tested. The crude antigen revealed 100% sensitivity, 94% specificity and 98% accuracy at the cut off level of 0.3 in acute infection. It gave positive results in 77% of chronic cases. Cross reactions with Schistosoma and Toxoplasma were negligible. A significant positive correlation between IHA titres and ELISA O.D. readings was observed. Fractions I and II proved of no diagnostic significance. The test system F. gigantica E/S product by IgM ELISA is highly recommended for diagnosis of acute fasciolosis.

Studies on human fascioliasis in Egypt. 1--Seasonality of transmission.

The present study aimed at investigating the seasonality of human fascioliasis. The monthly distribution of acute infection was studied together with the monthly Lymnaea cailliaudi snail density and infection Infection was observed in both snail and human host through out the year. However maximal snail infection was observed during the months of June and July while the number of acute human infections peaked in August. It was concluded that summer was the highest transmission season. The clinical incubation period was considered one or two months.

Studies on serum beta-glucuronidase activity and urinary tryptophan metabolites in human fascioliasis.

In the last few years, human fascioliasis has been reported more frequently from different parts of the world including Egypt. The present work aimed to study the ability of fascioliasis affected patients to metabolize tryptophan and to explore how this disease can affect the activity of the hydrolytic lysosomal enzyme beta-glucuronidase. Liver and kidney functions and complete blood pictures of the studied patients were considered. Eleven tryptophan metabolites together with 4-pyridoxic acid, the major metabolite of vitamin B6, were determined. Fascioliasis showed an abnormal pattern of tryptophan metabolism which resembled that described earlier by Kupke and Knapp and which indicated that those patients were suffering from vitamin B6 deficiency. This conclusion was proved by the decreased levels of 4-pyridoxic acid. Abnormally high levels of beta-glucuronidase were also encountered in the fascioliasis cases which points to the liver damage caused by the fluke.