Resistance of Plamodium falciparum to Antimalarial Drugs in Zaragoza (Antioquia, Colombia), 1998

Plasmodium falciparum sensitivity to chloroquine (CHL), amodiaquine (AMO) and sulfadoxine/pyrimethamine (SDX/PYR) was assessed in vivo and in vitro in a representative sample from the population of Zaragoza in El Bajo Cauca region (Antioquia-Colombia). There were 94 patients with P. falciparum evaluated. For the in vivo test the patients were followed by clinical examination and microscopy, during 7 days. The in vitro test was performed following the recommendations of the World Health Organization. The in vivo prevalence of resistance to CHL was 67%, to AMO 3% and to SDX/PYR 9%. The in vitro test showed sensitivity to all antimalarials evaluated. Concordance for CHL between the in vivo and in vitro tests was 33%. For AMO and SDX/PYR, the concordance was 100%. We conclude that a high percentage of patients are resistant to CHL (in vivo). A high rate of intestinal parasitism might explain in part, the differences observed between the in vivo and the in vitro results. Therefore, new policies and treatment regimens should be proposed for the treatment of the infection in the region. Nationwide studies assessing the degree of resistance are needed.

Evaluation of Three Mycobacterium leprae Monoclonal Antibodies in Mucus and Lymph Samples from Ziehl-Neelsen Stain Negative Leprosy Patients and their Household Contacts in an Indian Community

Mucus and lymph smears collected from leprosy patients (9) and their household contacts (44) in the Caño Mochuelo Indian Reservation, Casanare, Colombia, were examined with monoclonal antibodies (MoAb) against Mycobacterium leprae. The individuals studied were: 5 borderline leprosy (BB) patients, 4 with a lepromatous leprosy (LL), all of whom were undergoing epidemiological surveillance after treatment and 44 household contacts: 21 of the LL and 23 contacts of the BB patients. The MoAb were reactive with the following M. leprae antigens: 65 kd heat shock protein, A6; soluble antigen G7 and complete antigen, E11. All the samples were tested with each of the MoAb using the avidin-biotin-peroxidase technique and 3,3 diaminobenzidine as chromogen. The patients and household contacts studied were all recorded as Ziehl-Neelsen stain negative. The MoAb which showed optimal reaction was G7, this MoAb permited good visualization of the bacilli. Five patients with BB diagnosis and one with LL were positive for G7; of the BB patients' household contacts, 9 were positive for G7; 7 of the LL patients' household contacts were positive for the same MoAb. MoAb G7 allowed the detection of bacillar Mycobacterium spp. compatible structures in both patients and household contacts. G7 permited the visualization of the complete bacillus and could be used for early diagnosis and follow-up of the disease in patients.