Molecular detection of Entamoeba histolytica and Entamoeba dispar infection among wild rats in Kuala Lumpur, Malaysia

Entamoeba histolytica infection is the third-greatest parasitic disease responsible for death in the world. Wild rats harbouring E. histolytica can be the possible reservoir hosts for human amoebiasis. There were numerous studies on prevalence of intestinal parasites among wild rats in Malaysia but none has reported E. histolytica. Rats were captured from Sentul and Chow Kit areas, Kuala Lumpur, Malaysia. The preserved stool samples were used for microscopy examination and molecular analysis. Out of 137 samples collected, 12 were positive for E. histolytica / E. dispar / E. moshkovskii microscopically. Two E. histolytica (1.4%), 1 E. dispar (0.7%) and 6 mixed infections of E. histolytica and E. dispar (4.3%) were detected using PCR. This is the first report of molecular detection of E. histolytica/dispar infection among wild rats in Malaysia. This study provides useful information about the potential risks of zoonotic agents and the importance of developing control measures to prevent zoonotic transmission.

Prevalence of intestinal and blood parasites among wild rats in Kuala Lumpur, Malaysia

A survey was undertaken to investigate the prevalence of intestinal and blood parasites among wild rats in urban area of Kuala Lumpur, Malaysia. A total of 137 stool and blood samples were collected from wild rats from Sentul and Chow Kit areas. Five species of rats were captured and supplied by Kuala Lumpur City Hall. The most common was Rattus rattus diardii (Malayan Black rat), 67%, followed by Rattus norvegicus (Norway rat), 10%, Rattus argentiventer (rice-field rat), 10%, Rattus tiomanicus (Malaysian field rat), 9% and Rattus exulans (Polynesian rat), 4%. Rattus rattus diardii is commonly known to live in human environment and they are normally identified as pests to human community. More male rats were captured (61%) compared to female (39%). Out of 137 samples, 81.8% samples were positive with intestinal parasites, with 86.2% from Sentul area and 78.5% from Chow Kit area. Six different parasites were detected. The most common intestinal helminth parasite detected was Nippostrongylus brasiliensis (80.3%), followed by Hymenolepis nana (23.4%), Capillaria hepatica (13.9%) and Hymenolepis diminuta (2.9%). Intestinal protozoan detected was Entamoeba histolytica/E. dispar (8.8%). Trypanosoma lewisi (1.5%) was the only blood parasite detected.

Prevalence of scabies and head lice among children in a welfare home in Pulau Pinang, Malaysia

This is a survey of 120 children for scabies and head lice infestations in a welfare home in Pulau Pinang. Children from this welfare home (Rumah Kanak-Kanak Taman Bakti, Kepala Batas, Pulau Pinang) were randomly selected. Majority of them were Malays (72.5%) and the rest were Indians. The infestation rates were highest in the 10-12 years age group with 46% and 70% for scabies and head lice respectively. Head lice was more commonly seen in girls (65%) than boys (29%). Scabies was more commonly seen in boys (50%) than girls (16%). Overall prevalence rate for scabies was 31% and for head lice infestation was 49%.

A second case of diphyllobothriasis in Malaysia.

Diphyllobothriasis was first reported in Malaysia in 2002. We are reporting a second case of diphyllobothriasis in Malaysia. The patient was a 37-year-old Chinese male seen at the outpatient clinic with a complaint of passing strands of white color flat worm in his stool. He had no other abdominal complaints. Laboratory and physical examinations were normal. Diphyllobothrium latum was confirmed by examination of the gravid proglottids passed out and the typical operculated eggs expelled from the ruptured proglottids. The patient had a history of eating raw fish. He was treated with a single dose of praziquantel.

Acute cholecystitis caused by Clonorchis sinensis.

We are reporting a case of a 43-year-old Chinese male from Hong Kong, who came to see a doctor complaining of acute onset of severe upper abdominal pain. A diagnosis of acute cholecystitis was made and an emergency cholecystectomy was carried out. On opening the common bile duct, lancet-shaped worms were seen emerging from it. About 45 adult worms were collected and sent to the Department of Parasitology University of Malaya for identification. The worms were identified as Clonorchis sinensis. After the operation the patient was treated with praziquantel and he had an uneventful recovery.

Eye lesion caused by adult Brugia malayi: a first case reported in a child from Malaysia.

We are reporting a case of an eye lesion caused by an adult Brugia malayi. The patient was a 3-year-old Chinese boy from Kemaman District, Terengganu, Peninsular Malaysia. He presented with a one week history of redness and palpebral swelling of his right eye. He claimed that he could see a worm in his right eye beneath the conjunctiva. He had no history of traveling overseas and the family kept dogs at home. He was referred from Kemaman Hospital to the eye clinic of Hospital Tengku Ampuan Afzan, Kuantan, Pahang, Malaysia. On examination by the ophthalmologist, he was found to have a subconjunctival worm in his right eye. Full blood count revealed eosinophilia (10%). Four worm fragments, each about 1 cm long were removed from his right eye under general anesthesia. A thick blood smear stained with Giemsa was positive for microfilariae of Brugia malayi. A Brugia Rapid test done was positive. He was treated with diethylcarbamazine.

A retrospective prevalence study of malaria in an aborigine hospital in Gombak, Selangor, Malaysia.

This was a five-year retrospective study (1999-2004) on the prevalence of malaria at the Aborigine Hospital, Gombak, Malaysia. A total of 94 malaria cases was analysed. The highest case reports were for the year 2000, with 32 cases (34%), and the lowest was in 2004, with only 1 (1%). The majority of cases reported were among the Semai tribe (44%), followed by the Temiar tribe (34%) and the unspecified tribe (s) (20%). Females (53%) were more commonly affected than males (47%). The majority of cases were within the age group 1-5 years (51%). Plasmodium falciparum was the most common species reported in this study, at 57%, followed by Plasmodium vivax (38%) and 5% mixed infection of P. falciparum and P. vivax. Most patients (27%) stayed for more than one month in hospital. Most patients came from Kuala Lipis, Pahang, (78%). The most common complication was anemia (38%) followed by splenomegaly (18%); only 2% had cerebral malaria. All patients were treated with the standard anti-malarial drugs. No deaths were reported in this study.

Tuberculosis: a resurgent disease in immunosuppressed patients.

A total of 136 patients, 67 HIV, 69 diabetes mellitus (DM) with or without (+/-) end-stage renal disease (ESRD), were registered for tuberculosis treatment at the National Tuberculosis Center (NTBC) from May to December, 2003. Ages ranged from 21-78 years (median 57.7 years) in TB/DM patients, and 21-62 (mean 37.6 +/- 8.3 years) in TB/HIV patients. TB was significantly found in younger and single HIV patients, but in older and married DM patients (p<0.05). Male patients in both groups were strongly associated with TB, while females more commonly had TB with DM (p<0.05). The majority of these patients were Malays, unemployed, and resided in Kuala Lumpur territory; however, no statistically significant difference was found between the 2 groups. Smoking, IVDUs and hepatitis C virus (HCV) infection were more significantly found in TB/HIV patients and further analysis showed that pulmonary TB was strongly associated with HCV infection in these patients (p<0.05). Pulmonary TB (62; 89.9%) was the most common type found in both groups and was a markedly more common disease location in TB/DM patients, while extrapulmonary TB (21; 31.3%) and miliary TB (14; 21%) were significantly higher in TB/HIV patients. Cough with or without sputum, fever and loss of appetite and/or weight were common clinical presentations in both groups. Nevertheless, fever (54; 80.6%) and lymphadenopathy (17; 25.4%) were significantly related to TB/HIV patients (p<0.05). Interestingly, the presence of BCG vaccination and positive tuberculin skin test were stronger in TB/HIV (27; 40.3%) and TB/DM (20; 29%) patients, respectively (p<0.05). Overall, regular 6-, 9- and 12-months' anti-tubercular therapy (ATT) were routine practice, and EHRZ+B6 was the most common regimen used. The highest percentage of patients with treatment success were in both groups with 6 months' ATT; however, a significantly higher percentage was found in TB/DM (24; 34.8%) than TB/HIV (13; 19.4%) (p<0.05). A success rate of 15 (21.7%) was noted for TB/DM patients with 9 months' ATT, which was similar to both groups with the 12-month regimen. A higher percentage failure rate (lost to follow-up) was seen in TB/HIV (19; 28.4%) patients. Nine patients were reported to have anti-tubercular-drug side-effects, such as drug-induced hepatitis, blurred vision, and skin rash. No cases of drug resistance or death were notified among these patients.

A case of auricular myiasis in Malaysia.

Many cases of myiasis have been reported in Malaysia. This is the second reported case of auricular myiasis caused by Chrysomya bezziana. The patient was a 41-year-old, mentally retarded, Orang Asli man. He was brought to the clinic by his mother with a complaint of pain and bleeding in his right ear for 3 days. On examination, blood and multiple maggots were seen packed in the external auditory canal of the right ear. A total of 39 live maggots were removed and maintained until they developed into 3rd instar larvae, which were later processed and identified as Chrysomya bezziana. The patient was discharged with amoxicillin 500 mg three times a day for 1 week.

Retrospective prevalence of snakebites from Hospital Kuala Lumpur (HKL) (1999-2003).

A hospital based retrospective study of the prevalence of snakebite cases at Hospital Kuala Lumpur was carried out over a five-year period from 1999 to 2003. A total of 126 snakebite cases were recorded. The highest admission for snakebites was recorded in 2001 (29 cases). The majority of cases were admitted for three days or less (79%). Most of the snakebite cases were reported in the 11-30 years age group (52%). The male:female ratio was 3:1. The majority of cases were Malaysians (80%, 101 cases). Of the non-Malaysians, Indonesians constituted the most (56%, 14 cases). Bites occurred most commonly on the lower limbs (49%), followed by upper limbs (45%) and on other parts of the body (6%). No fatal cases were detected and complications were scarce. In 60% (70 cases) the snake could not be identified. Of the four species of snakes that were identified, cobra (both suspected and confirmed) constituted the largest group (25%), followed by viper (10%), python (4%) and sea snake (1%). The most common clinical presentations were pain and swelling, 92% (116 cases). All patients were put on snakebite charts and their vital signs were monitored. Of the snakebite cases, 48% (61 cases) were treated with cloxacillin and 25% (32 cases) were given polyvalent snake antivenom.

Tuberculosis in diabetic patients: a clinical perspective.

This retrospective and descriptive study was a report on the clinical situation of tuberculosis in diabetic patients, with 1,651 patients recruited. The mean age of TBDM patients was significantly higher than that of non-diabetic patients (p<0.05). Moreover, TBDM patients had a higher ratio of male to female than the other group. The significant proportion of TB appeared to increase steadily with age in diabetic patients compared to non-diabetic ones (p<0.05). However, they showed similarities in terms of sex, race, marital status, present address, and occupation. A higher percentage of pulmonary tuberculosis (91.4%) was shown in the TBDM group. We found that both groups had no differences in the radiological findings, with opacity or cavity of the upper lobe involvement being 89% and 91% in TBDM and non-diabetic groups, respectively. TBDM patients were shown to have more treatment success (33.3%), particularly the pulmonary type of tuberculosis in the longer duration ( 9 months). Further findings demonstrated that a lower proportion of the TBDM group defaulted in their treatment (19.8%) and experienced resistance to anti-tubercular therapy (1.4%) compared to non-diabetics.

Malaria: a 10-year (1994-2003) retrospective study at University Malaya Medical Center (UMMC), Kuala Lumpur, Malaysia.

Malaria is still one of the most important vector-borne diseases in Malaysia, particularly in remote areas. This retrospective study was carried out to find the prevalence of malaria among patients admitted to UMMC Kuala Lumpur, from 1994-2003. A total of 86 malaria cases were analyzed. Most cases occurred among foreigners [57% (49 cases)] while Malaysians constituted 43% (37 cases). Among foreigners, Indonesians constituted the most [57% (28 cases)]. Among Malaysians, most cases occurred among the Chinese [35% (13 cases)] followed by the Malays [30% (11 cases)]. Males [70%(60 cases)] were more commonly affected. The majority of cases were within the 20-39 year age group (69%). Three species of malaria parasites were reported, of which Plasmodium vivax constituted the most [55%( 47 cases)], followed by Plasmodium falciparum [29% (25 cases)], and only four cases (5%) of Plasmodium malariae. Nine percent (8 cases) were mixed infections. In this study, 12%(10 cases) developed chloroquine resistance: 7 cases of P. falciparum, and 3 cases of P. vivax. The most common complications were jaundice and anemia [77% (23 cases)], followed by blackwater fever [13% (4 cases)] and cerebral malaria [10% (3 cases)]. Most of the complications were due to P. falciparum [43% (13 cases)]. There were no reported deaths. This new source of malaria coming from foreigners must be given serious attention, as it has great potential of increasing malaria cases in urban Malaysia.

Occurrence of Cryptosporidium oocysts in Wrinkled Hornbill and other birds in the Kuala Lumpur National Zoo.

The occurrence of a coccidian parasite, Cryptosporidium, among birds in the Kuala Lumpur National Zoo was investigated in this study. A hundred bird fecal samples were taken from various locations of the zoo. Fecal smears prepared using direct smear and formalin ethyl acetate concentration technique were stained with modified Ziehl-Neelsen stain. Samples positive for Cryptosporidium with Ziehl-Neelsen stain were later confirmed using the immunofluorescence technique and viewed under the epifluorescence microscope. Six species of bird feces were confirmed positive with Cryptosporidium oocysts. They included Wrinkled Hornbill (Aceros corrugatus), Great Argus Pheasant (Argusianus argus), Black Swan (Cygnus atratus), Swan Goose (Anser cygnoides), Marabou Stork (Leptoptilos crumeniferus), and Moluccan Cockatoo (Cacatua moluccencis). These birds were located in the aviary and lake, with the Moluccan Cockatoo routinely used as a show bird. Results obtained in this study indicated that animal sanctuaries like zoos and bird parks are important sources of Cryptosporidium infection to humans, especially children and other animals.

Prevalence of cryptosporidiosis in HIV-infected patients in Kajang Hospital, Selangor.

A total of 66 fecal specimens obtained from patients infected with human immunodeficiency virus (HIV) from Kajang Hospital were screened for Cryptosporidium oocysts. The fecal specimens were concentrated using the formalin ethyl acetate concentration technique, stained with modified Ziehl-Neelsen and confirmed with immunofluorescence stain. It was established that 2 (3.0%) were positive for Cryptosporidium. The two cases involved a Chinese local man (with diarrhea) and an Indonesian foreigner (without diarrhea). A higher index of suspicion for clinical cryptosporidiosis in HIV patients, including those with chronic weight loss with or without diarrhea, is recommended. In addition, laboratory testing for Cryptosporidium in HIV-infected patients is highly recommended in order to have a better understanding of the epidemiology and management of the disease in Malaysia.

Prevalence of dengue fever and dengue hemorrhagic fever in Hospital Tengku Ampuan Rahimah, Klang, Selangor, Malaysia.

Dengue fever and dengue hemorrhagic fever have been known to be endemic and reportable diseases in Malaysia since 1971. Major outbreaks occurred in 1973, 1982 and in 1998. For the past few decades until now. many studies have been performed to investigate the importance of these two diseases in Malaysia. A retrospective study was carried out in Hospital Tengku Ampuan Rahimah Klang to find the prevalence of these diseases. The data was collected from the record department of this hospital starting from the year 1999 until 2003 (5 years). A total of 6,577 cases of dengue fever and 857 cases of dengue hemorrhagic fever were reported. From the year 2000 onwards, cases of dengue fever had increased tremendously. However for the year 2001, there was a slight decrease in the reported cases. Most cases occurred in 2003, increasing from 674 in 1999 to 2,813 in 2003. Highest incidence was seen in Malay males more than 12 years of age. However, the cases of dengue hemorrhagic fever declined tremendously throughout the years. Most cases occurred in 1999 with 674 cases, then declining to only one in the year 2001 before it increased to 60 and 72 in the years 2002 and 2003, respectively. Most cases occurred in patients above 12 years old, the majority of which were Malay males.

Parasitic infections in Malaysia: changing and challenges.

A total of 1,885 blood and stool samples of four main protozoan parasitic infections were retrospectively reviewed from January, 2000 to April, 2004. Eleven of the 1,350 stool samples were shown positive for Cryptosporidium and Giardia infections; one of the 5 cases was clinically diagnosed as gastrointestinal cryptosporidiosis, while 6 cases were giardiasis. In patients with giardiasis, children were among the high-risk groups, making up 66.7% of these patients. The common presenting signs and symptoms were: diarrhea (83.3%), loss of appetite (83.3%), lethargy (83.3%), fever (66.7%), nausea/vomiting (50.0%), abdominal pain (16.7%), dehydration (16.7%) and rigor and chills (16.7%). Metronidazole was the drug of choice and was given to all symptomatic patients (83.3%). For the blood samples, 28 of the 92 peripheral smears for Plasmodium spp infection were diagnosed as malaria. The age range was from 4 to 57, with a median of 32.5 years. The sex ratio (M:F) was 3.6:1, while the age group of 30-44 years was the most commonly affected in both sexes. The majority of patients were foreigners (60.7%) and non-professional (39%). Plasmodium vivax (71%) infection was the most common pathogen found in these patients, along with a history of traveling to an endemic area of malaria (31%). The predominant presenting signs and symptoms were: fever (27%), rigor and chills (24%), nausea/vomiting (15%) and headache (8%). Chloroquine and primaquine was the most common anti-malarial regimen used (78.6%) in these patients. The seroprevalence of toxoplasmosis in different groups was 258/443 (58%): seropositive for IgG 143 (32.3%); IgM 67 (15%); and IgG + IgM 48 (10.8%). The age range was from 1 to 85, with a mean of 34 (+/- SD 16.6) years. The predominant age group was 21 to 40 years (126; 28.4%). The sex ratio (M:F) was 1.2:1. Subjects were predominantly male (142; 32%) and the Malay (117; 26.4%). Of these, 32 cases were clinically diagnosed with ocular toxoplasmosis. The range of age was from 10 to 56 years with a mean of 30.5 (+/- SD 12.05) years. The sex ratio (M:F) was 1:1.7. The majority were in the age group of 21 to 40 years, female (20; 62.5%), and Malay (17; 53%). They were also single (16; 50%), unemployed (12; 37%), and resided outside Kuala Lumpur (21; 65.6%). The more common clinical presentations were blurring of vision (25; 78%), floaters (10; 31%) and pain in the eye (7; 22%). We found that funduscopic examination (100%) and seropositivity for anti-Toxoplasma antibodies (93.7%) were the main reasons for investigation. Choroidoretinitis was the most common clinical diagnosis (69%), while clindamycin was the most frequently used antimicrobial in all cases. Among HIV-infected patients, 10 cases were diagnosed as AIDS-related toxoplasmic encephalitis (TE) (9 were active and 1 had relapse TE). In addition, 1 case was confirmed as congenital toxoplasmosis.

Fasciolopsiasis: a first case report from Malaysia.

Fasciolopsiasis is a disease caused by the largest intestinal fluke, Fasciolopsis buski. The disease is endemic in the Far East and Southeast Asia. Human acquires the infection after eating raw freshwater plants contaminated with the infective metacercariae. There has been no report of fasciolopsiasis either in man or in animal in Malaysia. We are reporting the first case of fasciolopsiasis in Malaysia in a 39-year-old female farmer, a native of Sabah (East Malaysia). This patient complained of cough and fever for a duration of two weeks, associated with loss of appetite and loss of weight. She had no history of traveling overseas. Physical examination showed pallor, multiple cervical and inguinal lymph nodes and hepatosplenomegaly. Laboratory investigations showed that she had iron deficiency anemia. There was leukocytosis and a raised ESR. Lymph node biopsy revealed a caseating granuloma. Stool examination was positive for the eggs of Fasciolopsis buski. The eggs measure 140 x 72.5 microm and are operculated. In this case, the patient did not present with symptoms suggestive of any intestinal parasitic infections. Detection of Fasciolopsis buski eggs in the stool was an incidental finding. She was diagnosed as a case of disseminated tuberculosis with fasciolopsiasis and was treated with antituberculosis drugs and praziquantel, respectively.

Prevalence of intestinal parasites among members of the public in Kuala Lumpur, Malaysia.

A total of 246 stool samples were collected from the public who participated in a Medical Fair held at the University Malaya Medical Center. The stools were examined for intestinal parasites using the formalin-ether concentration technique. The overall infection rate was 6.9% (17 out of 246), with Trichuris trichiura being the most common parasite (4.5%), followed by Ascaris lumbricoides (0.8%), Clonorchis sinensis (0.8%), hookworm (0.4%), and Entamoeba histolytica (0.4%). None of these participants showed any clinical symptoms. The highest infection rate was among the Chinese 7.7% (13 out of 169), followed by the Malays 7.0% (3 out of 43) and Indians 3.3% (1 out of 30). The highest infection rate was in the age group 16-30 years, which was 9% (6 out of 67). The two cases of clonorchiasis were from two Chinese women aged 28 and 66 years. The 28-year-old Chinese woman was born in Malaysia and had never left the country, while the older woman was also born in Malaysia but had visited Hong Kong as a tourist on two occasions. Both enjoyed eating raw fresh water fish with porridge.

Prevalence of snake bites in Kangar District Hospital, Perlis, west Malaysia: a retrospective study (January 1999-December 2000).

The records of 284 snake bite cases presenting to the Kangar District Hospital, Perlis, west Malaysia, from January 1999 till December 2000 were carefully reviewed. Data on prevalence and types of snake bites, were recorded. The majority of the cases were among Malays (60.2%), followed by Chinese (16.9%), Indians (13%), and others which include Thai nationals, army personnel from Sabah and Sarawak, and foreign tourists (9.8%). A higher incidence was found in males (60.2%) and most cases were seen in the age group of 10-19 years (33%). Snake bites were more common between 2 PM and 9 PM (47.6%) and from 7 AM to 2 PM (33.4%). The snakes were positively identified in 68 cases, of which 50 were common cobras (Naja naja) (73%), 16 were Malayan pit vipers (Agkistrodon rhodostoma) (24%) and two were sea-snakes (3%).

Recombinant expression of Toxocara canis excretory-secretory antigen TES-120 in Escherichia coli.

The gene encoding the excretory-secretory antigen TES-120 of dog ascarid worm Toxocara canis was cloned into the bacterium Escherichia coli. The specificity of the recombinant TES-120 antigen produced by the bacterium was investigated. A total of 45 human serum samples from patients infected with differenthelminthes and protozoa, including 8 cases of toxocariasis, were tested against the recombinant antigens in immunoblot assays. The results from the assays revealed that the recombinant TES-120 antigen reacted with sera from toxocariasis patients only. This highly specific recombinant TES-120 antigen can potentially be used for the development of an inexpensive serodiagnostic assay for human toxocariasis.