The prevalence of Candida albicans-associated diarrhoea in Buea, South West Cameroon

A total of 362 stool specimens were collected from 184 and 178 patients presenting at the Buea district Hospital with and without diarrhoea, respectively. The samples were screened and cultured for Candida albicans using standard microbiological procedures. Of the 184 diarrhoeic stool cultures, 35.9% showed C. albicans overgrowth as indicated by count >or=10(4) CFL/mL. Of the 178 non diarrhoeic stool cultures, C. albicans was identified in 23.6% of samples and counts were all <10(4) CFU/mL. An association was observed for C. albicans overgrowth and diarrhoea (p<0.001). The majority of isolates (87.8%) from the 66 samples showing candida overgrowth were susceptible to Amphotericin B in anti-fungal drug sensitivity assays. Results of the study highly suggest that C. albicans is an important cause of diarrhoea in the study area. We recommend that this fungus should be routinely checked in individuals presenting with diarrhoea particularly children and patients on prolonged or frequent antibiotic therapy.     

Helicobacter pylori antigens in the faeces of asymptomatic children in the Buea and Limbe health districts of Cameroon: a pilot study

OBJECTIVE: To determine the prevalence and identify intra-familial risk factors associated with Helicobacter pylori infection in a paediatric population. METHODS: Cross-sectional study in the Buea and Limbe health districts, South West Cameroon. Stool samples were collected from 176 randomly selected apparently healthy children from two communities with different socioeconomic status. They comprised 86 males and 90 females aged 0-10 years with a mean age of 4.29. Helicobacter pylori status was determined using an enzyme-linked immunosorbent assay, the H. pylori stool antigen (HpSA) test. The test uses polyclonal anti-H. pylori capture antibody to detect H. pylori antigens in human stool. Epidemiological data were analysed using the Fisher test and odds ratio (OR) at 95% confidence intervals (CI). RESULTS: The overall prevalence of H. pylori was 52.27% (92 of 176). Univariate analysis showed that H. pylori prevalence was significantly higher in children of the low socioeconomic class, 62.50% (55 of 88) than in those of the high socioeconomic class, 42.05% (37 of 88) (P < 0.05; OR = 2.41, 95% CI: 1.26-4.64). Helicobacter pylori prevalence increased with age from 37.50% (12 of 32) for children aged <3 years, 50.00% (53 of 106) aged 3-6 years and 71.05% (27 of 38) aged 7-10 years (P > 0.05; OR = 0.81, 95% CI: 0.34-1.91). The frequency of infection was significantly higher in males, 64.00% (55 of 86) than in females, 41.11% (37 of 90), (P < 0.05; OR = 2.67, 95% CI: 1.39-5.17). CONCLUSIONS: This study highlights the continuing importance of age, sex and socioeconomic status in the acquisition of H. pylori infection.     

Dermatophytosis in schoolchildren in Ekpoma, Nigeria

Summary. Of 1400 pupils from two public primary schools in Ekpoma, Edo State, Nigeria, who were screened for dermatophyte infection, 188 (13.4%) were infected. The causative agents isolated included Microsporum audouinii in 88 (46.8%), Trichophyton mentagrophytes in 48 (25.5%), T. rubrum in 40 (21.3%), T. tonsurans in four (2.1%) and Epidermophyton floccosum in eight (4.3%). There were significant differences in the rate of infection between male and female schoolchildren as well as between children from different socioeconomic backgrounds.
Zusammenfassung. Unter 1400 Schulkindern der zwei Grundschulen in Ekpoma, Edo, Nigeria, die auf Dennatophyten-Infektionen untersucht wurden, erwiesen sich 188 (13,4%) infiziert. Die isolierten Erreger waren: Microsporum audouinii 88 (46,8%); Trichophyton mentagrophytes 48 (25,5%), T. rubrum 40 (21,3%), T. tonsurans 4 (2,1%) sowie Epidermophyton floccosum 8 (4,3%). Es waren deutliche Unterschiede in der Infektionsrate zwischen Jungen und Mädchen und auch zwischen Kindern unterschiedlicher sozio-ökonomischer Gruppen zu beobachten.     

Pseudomonas aeruginosa isolates recovered from clinical and environmental samples in Buea, Cameroon: current status on biotyping and antibiogram

OBJECTIVE: The study was aimed at determining the prevalent biotypes of Pseudomonas aeruginosa in the environment of Buea and the susceptibility of isolates to antibiotics. METHODS: One hundred and fifty clinical specimens (urine, wound and sputum) collected from patients attending various health institutions in Buea, and 50 environmental swabs from furniture, appliances and surroundings of these institutions were screened for P. aeruginosa using standard microbiological and biochemical methods. Antimicrobial susceptibility of the isolates was determined by the disc diffusion assay. RESULTS: Fifty-one (25.5%) of the 200 specimens were positive for the organism with urine (30%) being the most common source of isolation. Biochemical characterization grouped the isolates into eight biotypes with biotypes B III (25.59%), B II (23.53%) and B I (21.57%) being the most prevalent. Antimicrobial susceptibility results of isolates revealed 13 antibiotype patterns based on resistance to the antimicrobial agents investigated. The resistance pattern, cefotaxime, gentamicin and tetracycline (CTX(R) GEN(R) TET(R)) was the most common (21.6%) amongst the isolates. Over 40% of the isolates exhibited multi-drug resistance to five or more antibiotics, especially environmental isolates. However, there was a significant difference (P < 0.05) in the susceptibility of isolates to ciprofloxacin (98%), amikacin (90.2%) and netilmicin (80.4%) compared with other drugs used in the study. CONCLUSION: A combination of biotyping and antibiogram, which are relatively cheap and routinely available methods in our environment, could be useful for clinical and epidemiological studies particularly in laboratories in the developing world with limited resources.     

Volatile compounds in the stem bark of Sclerocarya birrea (Anacardiaceae) possess antimicrobial activity against drug-resistant strains of Helicobacter pylori

The aim of this study was to isolate and identify phytochemicals with anti-Helicobacter pylori activity from the stem bark of Sclerocarya birrea. The plant crude extract was fractionated by silica gel column and thin layer chromatography techniques, initially with ethyl acetate (EA) and subsequently with a combination of ethyl acetate/methanol/water (EMW). Further fractionation and identification of the phytoconstituents was achieved by gas chromatography and mass spectrometry (GC/MS) analysis. The antimicrobial activity of the fractions and compounds was evaluated against five metronidazole- and clarithromycin-resistant strains of H. pylori as well as a reference strain ATCC 43526 using the microbroth dilution technique. Amoxicillin was included in the experiments as a positive control antibiotic. Of the 18 fractions collected, 16 demonstrated anti-H. pylori activity with 50% minimum inhibitory concentration (MIC₅₀) values ranging from 310 μg/mL to 2500 μg/mL. Two of the fractions (EMW fraction 6 and EA fraction 1) revealed the presence of 5 and 24 compounds, respectively, representing 40.5% and 86.57% of the total composition. Most of the compounds were essential oils, with terpinen-4-ol being the most abundant agent (35.83%), followed by pyrrolidine (32.15%), aromadendrene (13.63%) and α-gurjunene (8.77%). MIC₅₀ ranges for amoxicillin, terpinen-4-ol and pyrrolidine were 0.0003-0.06 μg/mL, 0.004-0.06 μg/mL and 0.005-6.3 μg/mL, respectively. The inhibitory activities of terpinen-4-ol and pyrrolidine were similar to amoxicillin (P > 0.05). Most of these compounds are being reported in this plant for the first time and may represent new sources of therapeutically useful compounds against H. pylori.     

Molecular detection and drug resistance of Mycobacterium tuberculosis complex from cattle at a dairy farm in the Nkonkobe region of South Africa: a pilot study

Mycobacterium tuberculosis complex (MTBC) causes tuberculosis (TB) in humans and animals. We investigated the presence of MTBC in cattle milk and its drug resistance using polymerase chain reaction (PCR). Two hundred samples (100 mL each) were obtained from a dairy farm in the Nkonkobe region of South Africa. The samples were processed using the modified Petroff method. DNA was isolated using a Zymo Bacterial DNA kit and amplified using Seeplex(?) MTB Nested ACE assay. The Genotype(?) Mycobacterium tuberculosis-multidrug resistantplus (MTBDRplus) assay was used to perform drug susceptibility and detection of mutations conferring resistance to isoniazid (INH) and rifampicin (RIF). Eleven samples tested positive for MTBC DNA using the Seeplex(?) MTB Nested ACE assay. The Genotype(?) MTBDRplus assay showed that 10/11 samples were resistant to both INH and RIF i.e., multi-drug resistant (MDR). The most and least frequent rpoB mutations detected in RIF resistant samples were H526Y (9/10) and D516V (2/10) respectively. None of the INH resistant samples harbored mutations in the katG gene. However, all of them harbored the T8A mutation in the inhA gene. These results have clinical and epidemiological significance and calls for further studies and necessary actions to delineate the situation.     

Detection of Rickettsia africae in patients and ticks along the coastal region of Cameroon

Rickettsia africae was identified in seven (6%) of 118 patients with acute fevers of unknown etiology proven not to be malaria or typhoid fever from clinics along the coastal region of Cameroon by polymerase chain reaction (PCR) amplification and sequencing of the citrate synthase (gltA) and outer membrane protein A (ompA) genes of Rickettsia. The majority (71%) of the patients were female. Clinical manifestations included fever (100%), headache (71%), myalgia (71%), arthralgia (43%), pulmonary involvement (29%), and diffuse rash (14%). Moreover, R. africae was detected by PCR amplification and sequence analysis of the gltA and ompA genes in 62 (75%) of 83 adult Amblyomma variegatum ticks collected from cattle in the same region. These results confirm the presence of a previously unrecognized infectious disease in the indigenous Cameroonian population, as well as extend the established range of R. africae.     

Bacterial indicators of pollution of the Douala lagoon, Cameroon: Public health implications

Background

Indiscriminate disposal of untreated wastes which are often heavily laden with sewage microorganisms some of which are pathogenic to humans into aquatic environments near cities could serve as potential dangers to human health.

Objective

A prospective study was undertaken to investigate the scope of potential bacterial pathogens and to assess the extent of pollution of the Douala lagoon.

Methods

A total of eighty water samples were collected fortnightly from the lagoon at five stations from March to October 2005 and analysed for heterotrophic bacterial densities, coliform counts, faecal coliform and faecal streptococcal counts. Bacteria were isolated and identified using standard microbiology and biochemical techniques.

Results

High heterotrophic bacterial counts (33 × 10⁵ − 161 × 10⁵ CFU/ mL), total coliform counts (1.8 × 10² − 2.4 × 10² CFU/100 mL), faecal coliform counts (2.2 × 10² − 2.4 × 10² CFU/ 100 mL) and faecal streptococcal counts (2.1 × 102 − 2.3 x 10² CFU/100mL were observed in all sampling stations. Eleven species of bacteria: Bacteroides fragilis, Proteus vulgaris, Klebsiella pneumoniae, E. coli, Enterococcus faecalis, Enterobacter aerogenes, Citrobacter freundii, Aeromonas hydrophila, Pseudomonas aeruginosa, Bacillus mycoides and Serratia marcesens, were frequently isolated.

Conclusion

The presence of potential bacterial agents such as Bacteroides fragilis, Pseudomonas aeruginosa, Aeromonas hydrophila, Klebsiella pneumoniae and E. coli in the lagoon may pose a serious threat to the health and well being of users of the Lagoon and calls for urgent intervention.