Obtaining an isolate of Ancylostoma braziliense from dogs without the need for necropsy.

Isolation of a specific Ancylostoma species typically requires death of the source animal, or holding an animal long enough to collect feces after treatment, for worm recovery and identification. The reason for collecting worms is that the eggs are not easy to distinguish morphologically. In keeping with the 3 Rs of laboratory animal research (reduction, refinement, replacement), the objective of this study was to obtain an isolate of Ancylostoma braziliense from 1-time field-collected samples of canine feces without the need for killing the host. During a collection trip to Florida, fecal samples (n  =  148) were collected and identified as containing eggs of Ancylostoma species (n  =  64) using centrifugal sugar flotation. Eggs from hookworm-positive slides were washed into tubes, DNA was extracted, and 2 samples were identified as A. braziliense using restriction fragment length polymorphism (RFLP) with Hinf1. Larval cultures were initiated from these samples, and larvae from the cultures were returned to New York and used to inoculate a purpose-bred kitten with the goal of inhibiting the growth of any contaminating Ancylostoma caninum that might be present in the culture. The infection was patent at 15 days, and eggs were identified as A. braziliense by RFLP and DNA sequencing. Using forceps during endoscopy, 2 adult worms (1 male, 1 female) were recovered from the cat and identified morphologically as A. braziliense . Larvae were cultured from the feces of this cat and used to infect a laboratory-reared beagle dog. Additionally, worms recovered from the feces of the cat post-treatment were confirmed to be A. braziliense , except for 1 female A. caninum containing infertile eggs. The dog (patent 14 days post-infection) was also infected with A. braziliense as determined by RFLP and DNA sequencing of eggs and cultured larvae. Both the cat and dog were treated, verified to be no longer shedding eggs, and then placed into adoptive homes.

A human case of otoacariasis involving a histiostomatid mite (Acari: Histiostomatidae).

A 31-year-old Saudi man was seen at an ear, nose, and throat clinic at Riyadh, Saudi Arabia, with bilateral itching in the external auditory canal. On otoscopic examination, the skin lining the ear canal was thickened with whitish sheets of sloughed cells and thick discharge. Large numbers of mites of an undescribed species closely related to members of the genus Loxanoetus (Histiostomatidae) were present. The patient underwent successive washings of the ear canal with saline and 70% ethanol at intervals of 2-3 months and was treated with antibiotics. Treatment with Eurax (crotamiton) ear drops for one week cleared the mite infestation. This represents the first reported case of human otoacariasis involving a histiostomatid mite. Based on the known biology of histiostomatid mites and the associated hosts of Loxanoetus and related genera, there is reason to speculate that the patient acquired the infestation while swimming in a lake or pond where this mite was present.

Diphyllobothriasis in Saudi Arabia.

We described a Saudi patient infected with Diphyllobothrium latum D. latum. A 38-year-old male presented, complaining of passing worms. He had a history of recent travel to Europe and South East Asia. Stools examination revealed typical D. latum eggs. He was treated with praziquantel followed by saline purge, after which he discharged an intact tapeworm. Macroscopic and microscopic examinations of the worm confirmed the diagnosis of D. latum. This is the first case of diphyllobothriasis to be reported in Saudi Arabia. The epidemiology and methods of prevention of diphyllobothriasis are discussed.

Retrospective analysis of intestinal parasitic infections diagnosed at a University Hospital in Central, Saudi Arabia.

OBJECTIVE: To review the intestinal parasites diagnosed in a university hospital in Riyadh, Kingdom of Saudi Arabia (KSA). METHODS: This is a retrospective analysis of intestinal parasitic infections reported in patients visiting at King Khalid University Hospital (KKUH), Riyadh, KSA from 1996 to 2003. Information regarding positive cases detected during the study period was collected from the hospital records, using the Hospital Information System database of KKUH. The Statistical Package for Social Sciences was used for the statistical analysis. RESULTS: During this period, stools examination was carried out for a total of 63,892 patients, 1480 (2.3%) were positive for different intestinal parasites. Giardia lamblia was the most commonly reported parasite. The annual positivity rate for parasitic infections has decreased from 2.9-1.1%. CONCLUSION: Although this study was limited to hospital patients, comparison with previous reports indicates an overall decrease in the prevalence of intestinal infections in the study area.

Prevalence of Blastocystis hominis among "healthy" food handlers in Dammam, Saudi Arabia.

A prospective study was carried out to see the prevalence of B. hominis in food handlers in Dammam, Eastern Province of Saudi Arabia. A total of 17073 food handlers were examined, 8.50% persons were positive for this organism in their stool. In 2.4% of the food handlers, B. hominis was the only parasite, whereas in 1.9% and 4.2% of the cases, this organism was found in association with pathogenic and non pathogenic parasites respectively. We could find the correlation between the dietary habits and the presence of organism in stool. In 19.9% of the positive food handlers in whom rice was the predominant food the organism was seen, when compared to 80.1% of the predominantly wheat eaters.

An inguinal mass with local vascular lesions induced by a lymphatic filaria.

A 47-year-old Indian male presented with an inguinal mass clinically suspicious as a tumor. Histological examination of the excised mass demonstrated tissue reaction to degenerating intravascular adult filarial worms. The worms have been identified as a lymphatic filariae, most probably Wuchereria bancrofti. The case report underscores the need to maintain suspicion of genitourinary filarial lesions in non-endemic areas and describes atypical vascular lesions induced by lymphatic filariae.

Prevalence of hepatitis C virus among bilharziasis patients.

OBJECTIVE: Hepatitis C virus (HCV) infection with concurrent Schistosoma mansoni infestation has emerged as a major cause of chronic liver disease and liver cirrhosis. The aim of this study was to investigate the prevalence of HCV among bilharzia patients. METHODS: The study was conducted at the Viral Diagnostic and Parasitology Departments, Regional Laboratory and Blood Bank, Dammam, Kingdom of Saudi Arabia from August 1999 to July 2000. Sera from a total of 405 patients, including 356 Saudi nationals and 49 non-Saudis, who had a clinical suspicion of bilharziasis were tested, using enzyme linked immunosorbent assay for HCV infection and indirect hemagglutination tests for Schistosoma infestation. Diagnosis of schistosomiasis was made when serum anti-schistosoma antibody titer was either equal to or more than 1:256. RESULTS: A total of 39 cases out of 405 tested positive for bilharzia antibodies comprising of 22 (44.9%) non-Saudi and 17 (4.8%) Saudi individuals. Among these patients 7(17.9%) were found to have evidence of HCV infection. Of the 7 patients tested positive for HCV antibodies, there were 4 (26.7%) Egyptians, 2 (11.8%) Saudis and one (14.3%) Middle-Eastern. CONCLUSION: Our data shows that a good proportion (17.9%) of patients with bilharziasis had HCV infection. The percentage positive for HCV antibody were 26.7% in Egyptians, which is higher when compared to other nationals and Saudis.

Imported malaria infections diagnosed at the Malaria Referral Laboratory in Riyadh, Saudi Arabia.

OBJECTIVE: To determine epidemiological characteristics of imported malaria infections in Riyadh, Kingdom of Saudi Arabia, based on retrospective analysis of laboratory records within the Central Laboratory. METHODS: Records of the Malaria Referral Laboratory in Riyadh, Kingdom of Saudi Arabia (KSA) were reviewed for the past 6 years: 1416-1421 Hejri inclusive (1996-2001 Gregorian). The dates of blood films were converted to Gregorian calendar in addition to the Hejri dates already used in the records. Data collected included the date of film, age, sex, nationality and parasitological findings in the film. All data was entered and analyzed using statistical package for social sciences computer software. RESULTS: The annual mean number of positive slides was 212 +/- 78. Positive slides were reported at the rate of 18 /100,000 among 137,402 potential blood donors screened during this period. The overall slide positivity was 12.9% among suspected cases referred from hospitals and 9.5% among those referred from health centers and private clinics. Most positive slides were from Saudis (36.6%), Sudanese (30.9%), Indians (13.9%), Pakistanis (8%) and Yemenis (5%). The type of malaria infection varied in the different nationalities, reflecting the pattern of endemicity at the source of infection. Positive cases show a marked seasonality in Saudis, reflection seasonal transmission of the disease in the endemic areas. CONCLUSION: Although there is no active malaria transmission in Riyadh KSA, imported infections still poses a significant health problem. A high index of suspicion should be maintained in those with suggestive travel history. Efforts to reduce the incidence of transfusion malaria should aim at formulation of appropriate policies for selection of blood donors and for screening of blood.