Incidence of retinopathy of prematurity in very-low-birth-weight infants born at Kalafong Hospital, Pretoria

Introduction. Retinopathy of prematurity (ROP) is a complication of prematurity, is; diagnosed by ophthalmological screening of infants at risk (birth weight less than or equal to 1500 g), and may lead to blindness. The incidence of ROP is under-reported in developing countries, including South Africa. Published data from the USA (CRYO-ROP) show that black infants have a lower incidence of threshold ROP than their white counterparts (3.2% v. 7.4%). Preliminary results of a screening programme initiated at Kalafong Hospital in 1999 are reported. Aim. To determine the incidence of ROP in infants with a birth weight of less than or equal to 1500 g born at Kalafong Hospital. Patients and methods. Consecutive infants were enrolled at birth and screened for ROP 4 - 6 weeks later by indirect ophthalmoscopy. Repeat examinations were performed until vascularisation was complete or until the infant reached a postconceptional age of 40 weeks. Infants with stage 3 ROP who developed threshold disease were treated with cryotherapy or laser therapy. Results. One hundred and forty-five infants were enrolled over 10 months (15 February 1999 - 25 December 1999); of these 94 were screened. Of the remaining 51 infants, 24 died before screening and 27 were discharged before screening and were lost to follow-up. ROP was diagnosed in 23 of the 94 infants screened (24.5%). Stage 1 and 2 ROP occurred in 17 of the infants screened (18.1%) and stage 3 ROP in 6 (6.4%), of whom 4 (median birth weight 995 g, range 900 - 1450 g) developed threshold ROP and were treated. Conclusions. The incidence of ROP in black very-low-birthweight infants born at Kalafong Hospital is 24.5%. The incidence of threshold ROP is 4.3% (3.2% in infants less than or equal to 1250 g) and correlates with published data from the USA. Infants with a birth weight less than or equal to 1500 g should receive opthalmological screening to diagnose stage 3 ROP timeously.