IL-6 is Upregulated in Late-Stage Disease in Monkeys Experimentally Infected with Trypanosoma brucei rhodesiense

The management of human African trypanosomiasis (HAT) is constrained by lack of simple-to-use diagnostic, staging, and treatment tools. The search for novel biomarkers is, therefore, essential in the fight against HAT. The current study aimed at investigating the potential of IL-6 as an adjunct parameter for HAT stage determination in vervet monkey model. Four adult vervet monkeys (Chlorocebus aethiops) were experimentally infected with Trypanosoma brucei rhodesiense and treated subcuratively at 28 days after infection (dpi) to induce late stage disease. Three noninfected monkeys formed the control group. Cerebrospinal fluid (CSF) and blood samples were obtained at weekly intervals and assessed for various biological parameters. A typical HAT-like infection was observed. The late stage was characterized by significant (P<0.05) elevation of CSF IL-6, white blood cell count, and total protein starting 35 dpi with peak levels of these parameters coinciding with relapse parasitaemia. Brain immunohistochemical staining revealed an increase in brain glial fibrillary acidic protein expression indicative of reactive astrogliosis in infected animals which were euthanized in late-stage disease. The elevation of IL-6 in CSF which accompanied other HAT biomarkers indicates onset of parasite neuroinvasion and show potential for use as an adjunct late-stage disease biomarker in the Rhodesian sleeping sickness

Herbal Medicines in Kenya: A Review of the Toxicity and Quality Control Issues

In sub-Saharan Africa, it is estimated that 80% of the population depends on indigenous medicines for primary health-care. These herbs often contain highly active pharmacological compounds whose pharmacotherapeutic and toxicity profiles have not been well characterized. Toxicity may be related to several intrinsic and extrinsic factors. Most of the available reports related to the toxic effects of herbal medicines cite hepatoxicity as the most frequently experienced toxicity. However, noxious effects involving kidneys, the nervous system, skin, blood, the cardiovascular system, mutagenicity and carcinogenicity have also been published. This article presents a systematic review on safety and toxicity of herbal medicines used in Kenya. Keywords: Herbal medicine, herbal preparations, toxicity, Kenya, regulations, complementary and alternative medicin

Organ Pathology and Associated IFN-γ and IL-10 Variations in Mice Infected with Toxoplasma gondii Isolate from Kenya

Toxoplasma gondii is an important foodborne opportunistic pathogen that causes a severe disease in immunocompromised patients. The pathology and immune responses associated with the ensuing disease have not been well described in strains from different parts of the world. The aim of the present study is to determine the IFN-γ and IL-10 variations and organ pathology in immunocompetent and immunocompromised mice infected with T. gondii isolated from a Kenyan chicken. Two groups of BALB/c mice were infected with T. gondii cysts and administered with dexamethasone (DXM) in drinking water. Other two groups: infected untreated and uninfected mice were kept as controls. The mice were euthanized at various time points: blood collected for serum and assayed for IFN-γ and IL-10 variations. After infection, significant (p<0.05) elevated levels of IFN-γ and IL-10 were observed. A significant decline in IFN-γ and IL-10 levels (p<0.05) was observed after dexamethasone treatment. Histological sections in the liver, heart, and spleen of the mice administered with DXM revealed various degrees of inflammation characterized by infiltration of inflammatory cells. The dexamethasone-treated mice presented with progressively increased (p<0.001) inflammatory responses is compared with the infected untreated mice

Influence of Cyclophosphamide on the Haematological Profile of Laboratory Bred African Soft-furred Rats (Mastomys natalensis)

The African soft-furred rat (Mastomys natalensis) has been shown to be a possible model for propagation  of Trypanosoma brucei gambiense. This study aimed at determining the baseline biological reference values  and reproductive data of a laboratory bred Mastomys colony, which was established at TRC. In addition,  the effect of cyclophosphamide (an immunosuppressant) treatment (s) on the haematological profile  was investigated. The mean gestation period was 23 days and the mean litter size was eight. At birth, the  pups weighed 2.4±0.23 g and the weights increased to 78.0±10.6 g in males and 53.9±4.5 g in females by  90 days. The mean haematological values were significantly (p&lt;0.05) higher in adults than juveniles.  However, there was no statistical difference of haematological values between the sexes.  Cyclophosphamide treatment caused a macrocytic hypochromic anaemia, which was noted 24 hours after  treatment and was more severe in animals treated more than once. Thus, in studies involving a disease that  causes anaemia, repeated cyclophosphamide treatment should be limited. Our study is a contribution to  the clinical and biological characterization of the disease pattern in this preferred rodent model of T. b.  gambiense.

Prevalence and Types of Coinfections in Sleeping Sickness Patients in Kenya (2000/2009)

The occurrence of coinfections in human African trypanosomiasis (HAT) patients was investigated using a retrospective data of hospital records at the National Sleeping Sickness Referral Hospital in Alupe, Kenya. A total of 31 patients, 19 males and 12 females, were diagnosed with HAT between the years 2000 and 2009. The observed co-infections included malaria (100%), helminthosis (64.5%), typhoid (22.5%), urinary tract infections (16.1%), HIV (12.9%), and tuberculosis (3.2%). The species of helminthes observed included Ancylostoma duodenale (38.7%), Ascaris lumbricoides (45.7%), Strongyloides stercoralis (9.7%), and Taenia spp. (3.2%). The patients were also infected with Entamoeba spp. (32.3%) and Trichomonas hominis (22.6%) protozoan parasites. The main clinical signs observed at the point of admission included headache (74.2%), fever (48.4%), sleep disorders (45.2%), and general body pain (41.9%). The HAT patients were treated with suramin (early stage, 9/31) and melarsoprol (late stage, 22/31). In conclusion, the study has shown that HAT patients have multiple co-infections which may influence the disease pathogenesis and complicate management of HAT

Use of the nested polymerase chain reaction for detection of Toxoplasma gondii in slaughterhouse workers in Thika District, Kenya

Background. The widely used methods of diagnosis of Toxoplasma gondii are serological. Current reports indicate a high seroprevalence of T. gondii in humans in Kenya. There is a need for more sensitive diagnostic tests, especially when the specific antibody titres are below detectable threshold levels. Use of the polymerase chain reaction (PCR) targeting the repetitive 529 base pair loci has been reported to be sensitive and specific.Objective. To detect T. gondii in a high-risk group of public health workers in Thika District, Kenya.Methods. In total, 87 human blood samples were collected from male slaughterhouse workers between 1 March 2013 and 25 June 2013. The DNA extracted was amplified by the nested PCR.Results. T. gondii was detected in 39.1% (34/87) of the workers. In the cow-sheep-goat slaughterhouses the prevalence ranged between 20% and 60%, while all the chicken slaughterhouse workers (6/6, 100%) tested positive. The difference in T. gondii positivity between the workers in the chicken slaughterhouse and those in the cattle-sheep-goat slaughterhouses was statistically significant (p=0.003).Conclusion. This study shows the presence of T. gondii in an asymptomatic high-risk group in Thika District, indicating the need for enhancement of public health awareness

Pathogenicity of bloodstream and cerebrospinal fluid forms of Trypanosoma brucei rhodesiense in Swiss White Mice

Trypanosoma brucei rhodesiense (T.b.r.), the causative agent of the East African form of human African trypanosomiasis (HAT), is capable of crossing the blood brain barrier and invade the central nervous system (CNS). However, it is not clear whether bloodstream forms (BSF) of T.b.rhodesiense differ in biological characteristics from the cerebrospinal fluid (CSF) forms. The present study was carried out to compare the pathogenicity of CSF and BSF of T.b. rhodesiense parasites in Swiss white mice following intraperitoneal inoculation with 106 trypanosomes. The parasites were tested for presence of the serum resistance associated (SRA) gene. Parasitaemia, body weight, packed cell volume (PCV) and survival of the mice was monitored daily until the experiment was terminated. Data was analyzed using general linear model. Both forms of parasite were positive for the SRA gene, and there was no significant difference in progression of parasitaemia, PCV values or survival of the mice. However, the weights of BSF infected mice initially dropped faster than those of CSF infected mice (P&lt;0.001)

Haematology of Experimental Trypanosoma Brucei Rhodesiense Infection in Vervet Monkeys

Haematological aberrations associated with human infective trypanosomes were investigated in the vervet monkey model of the Rhodesian sleeping sickness. Four monkeys were infected intravenously with 104 Trypanosoma brucei rhodesiense and monitored for changes in the blood profile using a haematological analyser. A chronic infection lasting between 48 and 112 days was observed. Microcytic hypochromic anaemia, which was characterized by a decline in packed cell volume (PCV), red blood cell (RBC) numbers, mean corpuscular volume (MCV) and mean corpuscular haemoglobin concentration (MCH) developed at an early stage, and persisted throughout the infection. The mean platelet counts declined significantly from 3 x 105/\u3bcl (day 0 post infection) to 6.8 x 104/\u3bcl (day 7 post infection) and remained low in all the animals. However, the mean platelets volume rose during the course of the infection. An initial decline in total white blood cell (WBC) counts occurred between day 0 and 7 (3.1 x 106/\u3bcl) and remained low up to day 35 post infection (3.5 x 106/\u3bcl). This was followed by an increase in WBC counts, principally associated with increased lymphocyte numbers. It is concluded that microcytic hypochromic anaemia, thrombocytopaenia and an initial leucocytopaenia are the most important haematological changes associated with a chronic infection of T.b. rhodesiense infection in vervet monkeys

Use of the nested polymerase chain reaction for detection of Toxoplasma gondii in slaughterhouse workers in Thika District, Kenya

Background. The widely used methods of diagnosis of Toxoplasma gondii are serological. Current reports indicate a high seroprevalence of T. gondii in humans in Kenya. There is a need for more sensitive diagnostic tests, especially when the specific antibody titres are below detectable threshold levels. Use of the polymerase chain reaction (PCR) targeting the repetitive 529 base pair loci has been reported to be sensitive and specific.Objective. To detect T. gondii in a high-risk group of public health workers in Thika District, Kenya.Methods. In total, 87 human blood samples were collected from male slaughterhouse workers between  1 March 2013 and  25 June 2013. The DNA extracted was amplified by the nested PCR.Results. T. gondii was detected in 39.1% (34/87) of the workers. In the cow-sheep-goat slaughterhouses the prevalence ranged between 20% and 60%, while all the chicken slaughterhouse workers (6/6, 100%) tested positive. The difference in T. gondii positivity between the workers in the chicken slaughterhouse and those in the cattle-sheep-goat slaughterhouses was statistically significant (p=0.003).Conclusion. This study shows the presence of T. gondiiin an asymptomatic high-risk group in Thika District, indicating the need for enhancement of public health awareness.