[1] Univ Yaounde I, Fac Med & Biomed Sci, Dept Internal Med & Specialties, Yaounde, Cameroon
[2] Univ Yaounde I, Univ Teaching Hosp Yaounde, Yaounde, Cameroon
[3] Univ Yaounde I, Fac Med & Biomed Sci, Yaounde, Cameroon
[4] South African Med Res Council, Cape Town, South Africa
[5] Univ Cape Town, ZA-7925 Cape Town, South Africa
[6] Univ Yaounde I, Yaounde Gen Hosp, Yaounde, Cameroon
[7] Univ Yaounde I, Fac Med & Biomed Sci, Dept Obstet & Gynecol, Yaounde, Cameroon
[8] Univ Douala, Fac Med & Pharmaceut Sci, Dept Internal Med, Douala, Cameroon
[9] Univ Douala, Douala Gen Hosp, Douala, Cameroon
[10] Univ Yaounde I, Fac Med & Biomed Sci, Dept Biochem & Physiol Sci, Yaounde, Cameroon