Finding the missing children for TB care and prevention in Kenya

SETTING: One hundred high TB burden facilities in nine counties in Kenya.OBJECTIVES: 1) To increase uptake of TB preventive therapy (TPT) among child contacts aged <5 years, and 2) to increase TB diagnosis in children aged <15 years presenting to health facilities for routine care.DESIGN: For objective 1, a clinic-based child contact management strategy incorporating transport/healthcare cost reimbursement, monitoring and evaluation tools, and healthcare worker education was utilized. For objective 2, community health screeners were established in pediatric outpatient departments to perform verbal screening, flagging symptomatic children for further evaluation.RESULTS: Over 15 months, identification of 8,060 individuals diagnosed with bacteriologically confirmed TB led to 2,022 child contacts. Of these, 1,848 (91%) were evaluated; 149 (8%) were diagnosed with TB disease, leaving 1,699 (92%) eligible for TPT; 1,613 (95%) initiated TPT and 1,335 (83%) completed TPT. In outpatient settings, 140,444 children were screened; 54,236 (39%) had at least two TB symptoms; 2,395 (4%) were diagnosed with TB diseaseCONCLUSION: Health system strengthening supporting a clinic-based child contact management program increased the number of children initiating TPT. Systematic screening in outpatient clinics can lead to increased TB case notifications; however, optimal screening tools and clearer diagnostic pathways for the evaluation of these children are needed.

TB training in Kenya: building capacity for care and prevention

BACKGROUND: Devolution of healthcare services in Kenya resulted in a large number of newly recruited tuberculosis (TB) coordinators. We describe a unique collaboration between a national tuberculosis program (NTP), a local, and an international non-governmental organization to build human resource capacity in TB care and prevention.METHODS: From 2016 to 2021, the Kenya Division of National Tuberculosis, Leprosy and Lung Disease Program, Centre for Health Solutions-Kenya, and the International Union Against Tuberculosis and Lung Disease developed and conducted a series of 7-day training courses. A key focus of training was the introduction of TBData4Action, an approach involving the local use of routinely available data to strengthen decision-making and support supervision.RESULTS: Implementation outcomes included training 331 (96%) coordinators out of 344, representing all 47 counties, 37 national officers and 21 other stakeholders using the country-tailored curriculum, including hands-on group work by county teams and field practicals. Thirty-five national facilitators were identified and mentored as local faculty. Training costs were reduced by 75% compared with international alternatives.CONCLUSION: The collaboration resulted in the training of the majority of the coordinators in a standardized approach to TB care. A sustainable approach to capacity building in local data use was found feasible; the model could be adapted by other NTPs.

Enhancement of eosinophil-mediated cytotoxicity to schistosomula of Schistosoma mansoni by autologous mononuclear cells from patients

Adherent mononuclear cells (monolayer), when co-cultured with autologous peripheral blood eosinophils isolated from patients treated for Schistosoma mansoni infections, enhanced the eosinophil-mediated killing of antibody coated schistosomula. The monolayer increased the activity of the eosinophils by 225%, and was observed in 80% of the patients studied. Heat labile factors other than complement, present in immune serum, further enhanced the ability of eosinophils to kill schistosomula in the presence of the monolayer. On their own the adherent cells did not mediate obvious damage to the parasite. Eosinophils that had been pre-incubated with the monolayer (100 mins) and tested separately, killed equal numbers of schistosomula as in the co-culture assay; this excludes the possibility of concurrent schistosomula cytotoxicity by the two cell populations. The ability of the monolayer to activate eosinophils was not altered by inhibitors of protein synthesis. The monolayer was largely consistent of monocytes as demonstrated by an over 96% positive staining for non-specific esterases.

Immune responses after treatment for Schistosoma mansoni infections

The changes in the immune responses of patients before and at 3 weeks after treatment with anti-schistosomal drugs were investigated. Lymphocyte responses to Concanavalin A and to worm antigens were inhibited after treatment, whereas responses to cercarial and egg antigens remained unchanged. Eosinophil levels were significantly elevated after treatment and were positively correlated with the increase in anti-worm antibodies (r = 0.587), and negatively associated with anti-egg antibodies (r = -0.727). Although the eosinophil-dependent cytotoxicity to schistosomula was not significantly enhanced after treatment, some increased killing was evident of half the patients (7/15). On the other hand, the ability of adherent mononuclear cells to stimulate eosinophil functions was markedly enhanced by treatment (P less than 0.001). These studies suggest that treatment may enhance some of the potentially protective host's immune mechanisms.

Eosinophilia and eosinophil helminthotoxicity in patients treated for Schistosoma mansoni infections

The changes in eosinophil levels and in eosinophil-mediated antibody-dependent schistosomular cytotoxicity, following treatment for Schistosoma mansoni infections, have been investigated in 2 similar groups of patients aged 15-50 years. Patients in group 1 were treated with either hycanthone or oxamniquine, and those in group 2 with hycanthone or praziquantel. Eosinophil levels were significantly increased in both groups. In group 1 peripheral blood eosinophil counts rose from a mean of 175/microliters before treatment to 745/microliters 3 weeks after treatment, and in group 2 from 181/microliters to 1066/microliters. The increase in eosinophil levels was positively correlated with a rise in circulating anti-adult worm antibodies (r = -0.587, P less than 0.05), whereas a negative correlation was recorded with anti-egg antibodies (r = -0.727). Despite some enhanced eosinophil helminthotoxicity following treatment in some of the individuals in group 1 (7/15), the change overall was not significant. In group 2, in which a different standard anti-schistosomular antibody was used, the eosinophil killing capacity recorded at 3 weeks was lower than that before commencement of treatment (t = 2.89, P less than 0.01). The eosinophil stimulating activity, detected in cultured mononuclear cell supernatants (MCS) from individual patients, correlated with eosinophil levels (r = 0.582, P less than 0.02) but there was no association with eosinophil killing. MCS activity did not appear to be boosted by treatment. These studies showed that peripheral blood eosinophil counts were increased following treatment, but their ability to kill schistosome larvae is variable and may depend on the immune serum used as the source of anti-schistosomular antibody.