Combination Activity of Standard Antituberculosis Drugs and Extracts of Medicinal Plants Commonly Used in Traditional Treatment of Tuberculosis in Uganda

Introduction: Resistance to antituberculosis drugs and adverse drug reactions remain the leading causes of tuberculosis therapeutic failure globally. Despite the increasing acceptance of medicinal plant use in combination with conventional antituberculosis drugs in treatment of tuberculosis (TB) in Uganda, there is paucity of knowledge on their combination effect. Aim: This research aimed to determine combination activity of standard antituberculosis drugs with extracts of Zanthoxylum leprieurii Guill. & Perr. and Rubia cordifolia L., the two common antituberculosis medicinal plants in Uganda, against pansensitive (H37Rv) and multi-drug resistant (MDR) Mycobacterium tuberculosis strains. Materials and Methods: Two reference MTB strains (H37Rv and MDR strain) were inoculated on Middlebrook 7H11 medium containing a combination of standard antituberculosis drugs and methanol extracts of Z. leprieurii and R. cordifolia at varying concentrations. The number of colonies on the plates was observed and counted weekly for up to 8 weeks. In vitro combination activity was determined using proportion method. Mean percentage inhibition was calculated for the reduction of number of colonies on drug-extract combination medium in relation to drug-extract-free control medium. Results: Drug-extract combinations showed good combination activity against Mycobacterium tuberculosis strains when compared with individual standard anti-TB drugs. This was more exhibited against MDR strain. There was however a reduction in percentage inhibition when extracts were combined with ethambutol and streptomycin against H37Rv strain. Conclusions: Zanthoxylum leprieurii and Rubia cordifolia in combination with standard anti-TB drugs exhibited increased in vitro activity against Mycobacterium tuberculosis, especially MDR-TB strain. This justifies the local use of these plants in traditional treatment of tuberculosis especially in resistant cases in Uganda.

Anti-Mycobacterial Activity of Medicinal Plant Extracts Used in the Treatment of Tuberculosis by Traditional Medicine Practitioners in Uganda

Tuberculosis (TB) remains a public health challenge and one of the leading causes of death worldwide. TB is preventable and curable. However, treatment of tuberculosis has continued to be difficult as a result of rapid increase of multidrug and extensively drug resistant strains of Mycobacterium tuberculosis. Medicinal plants have for centuries been traditionally used in treatment of tuberculosis and similar ailments. They possess antimicrobial properties which render them a new hope as a source of novel bioactive leads in the development of antimycobacterial agents. In this study, 2 plant species commonly used traditionally in Uganda for treatment of tuberculosis, Zanthoxylum leprieurii and Rubia cordifolia were screened for in vitro antimycobacterial activity against Mycobacterium tuberculosis strains;pan sensitive MTB H37Rv, Rifampicin resistant TMC 331 strain and two wild strains (one rifampicin resistant and another one rifampicin susceptible). Antimycobacterial activity of aqueous, ethanolic and methanolic plant extracts was determined using Resazurin Microtiter Assay (REMA). Both plant extracts exhibited significant in vitro antimycobacterial activity against all strains of Mycobacterium tuberculosis. Minimum inhibitory concentrations (MIC) of methanolic crude extracts of both plants ranged from 23.4 μg/mL to 187.5 μg/mL. Comparatively, methanol extracts of both plants possessed superior antimycobacterial activity against all Mycobacterium tuberculosis strains. Our findings indicated that both plants exhibited activity against susceptible and resistant strains of Mycobacterium tuberculosis. While antimycobacterial activity of Z. leprieurii confirms results from previous studies, activity of the extracts of R. cordifolia is reported for the first time in East Africa. Further studies aimed at determining the effects of combination of these plant extracts and standard anti-TB drugs should be carried out.

Incidence and Etiology of Catheter Associated Urinary Tract Infection among Admitted Patients at Kabale Regional Referral Hospital, South Western Uganda

Introduction: Catheter Associated Urinary Tract Infection is the most common hospital acquired infection worldwide. Urinary Tract Infections among catheterised patients are on rise regardless of antibiotic use and this is due to erratic use of antibiotics, treatment failure, antimicrobial resistance and emergency of Extended Spectrum Beta Lactamase producing bacteria leading to patient distress, increased healthcare costs, long hospital stay and poor patient response to antibiotics. In Uganda, no previous studies have sought to study the burden of CAUTI among catheterized patients, the bacterial pathogens involved and their antimicrobial susceptibility patterns yet there is upsurge in antimicrobial resistance of uropathogens. The effective management of patients suffering from Catheter Associated Urinary Tract infection (CAUTI) relays on the identification of uropathogens that cause CAUTI and the selection of an effective antibiotic agent to the uropathen in question. Objectives: The objectives of this study were to determine incidence, etiology and antibiotic susceptibility pattern among the uropathogens causing Catheter Associated Urinary Tract Infections among patients with indwelling catheters at Kabale Regional Referral Hospital. Methods: Using a descriptive prospective observational hospital-based study, the study was conducted on 150 catheterized patients recruited from Emergency, Obstetrics and gynecology, Medical, Maternity and Surgical wards at Kabale Regional Referral Hospital between April and May 2019. The urine samples from study participants were processed in Kabale RRH microbiology laboratory as per standard operating procedures. After isolation and identification, all the isolates were subjected to antibiotic susceptibility testing for commonly used antibiotics. Results: Following the urine culture from 150 catheterized patients, urine from 23 (15.3%) patients showed significant growth. The common bacterial isolates were Escherichia coli 12 (52%), followed by the Klebsiella pneumoniae 6 (26%), Staphylococcus aureus 3 (13%) and Pseudomonas spp. 2 (8.7%). All Gram-negative isolates were sensitive to Imipenem 20 (100%) while all S. aureus isolates (3) were 100% sensitive to Vancomycin and Cefoxitin. Isolates were sensitive to Gentamicin 20 (82.6), Ceftriaxone 16 (69.6), Ciprofloxacin 10 (43.5) and Nitrofurantoin 9 (39.1). All isolates were 100% resistant to Cotrimoxazole. 6 gram negative isolates were resistant to ceftazidime and were tested for Extended Spectrum Beta (ß) Lactamase (ESBL), 5 (83.3%) were identified as ESBL-producing bacteria. K. pneumonia 3 (60%) presented the highest percentage of ESBLs as compared to E. coli 2 (40%). Conclusions: The Incidence of CAUTI among patients with indwelling urinary catheters at Kabale Regional Referral Hospital is high (15.3%) and is mostly caused by E. coli and K. pneumoniae. These bacteria are resistant to most commonly used antibiotics and thus there is a need to put more emphasis on CAUTI prevention strategies and use culture and sensitivity tests before prescription of antibiotics.

Clindamycin Resistance among Methicillin Resistant <i>Staphylococcus aureus</i>Isolated from Human and Respective Household Swine in Greater Kabale Region—South Western Uganda

Introduction: S. aureus is recognized as the common cause of nosocomial and community-acquired infections. Macrolide-Lincosamide-Streptogramin B (MLSB) is thought to be alternative therapies against MRSA infections. Clindamycin is the most favored agent because of exceptional pharmacokinetic characteristics. However, increasing resistance to clindamycin among MRSA strains is a serious challenge. The current study investigated the profile of clindamycin resistance among MRSA isolates from Humans, and their respective livestock (in particular swine) using D-test in greater Kabale region. Materials and Methods: Three hundred phenotypic MRSA isolates previously isolated from Humans and swine were confirmed by mecA PCR. We performed D-test using erythromycin (15 μg) and clindamycin (2 μg) discs in accordance to Clinical and Laboratory Standards Institute (CLSI) protocol. Results: Of all 300 MRSA isolates, 6% (n = 18) were sensitive to Erythromycin and Clindamycin (S). The rate of inducible clindamycin resistance (iMLSB) was 42% (n = 125) and 38% (n = 115) was resistance to both Erythromycin and clindamycin (cMLSB). However, 14% (n = 42) were resistant to erythromycin but sensitive to clindamycin (MS) without “D” zone negative. Conclusion: Clindamycin resistance (both cMLSB and iMLSB) among MRSA was high and “D” test should be adopted routinely during antimicrobial susceptibility testing by disc diffusion testing to rapidly detect iMLSB and cMLSB.