J Pediatr Endocrinol Metab 2017; 30(9): 973–978 Majid Valizadeh, Farzaneh Moezzi, Zohreh Khavassi, Mohammad Movahedinia*, Seideh Mazloomzadeh and Ladan Mehran Influence of topical iodine-containing antiseptics used during delivery on recall rate of congenital hypothyroidism screening program https://doi.org/10.1515/jpem-2016-0164 Received April 29, 2016; accepted July 17, 2017; previously published online August 15, 2017 Abstract Background: The proportion of newborns recalled during neonatal screening programs for congenital hypothyroid- ism (CH) varies substantially by country and may be higher in settings where povodine iodine (PVP-I) is used during delivery. We assessed this hypothesis by substituting PVP-I for chlorhexidine (CHL) and evaluated the reduction in the recall rate of the Irainian newborn screening program. Methods: This study investigated 2282 neonates of mothers admitted to a local hospital for delivery between Decem- ber 2012 and October 2013. We measured thyorid stimulat- ing hormone (TSH) levels in heel-prick blood specimens of infants, aged between 3 and 5 days, born to mothers who received PVP-I (phase I) and those who received CHL after withdrawal of PVP-I from obstetric procedures (phase II). Then we compared the median TSH levels and the recall rate based on a TSH level ≥5 mU/L. Results: Of 2282 cases, 1094 infants were born to mothers exposed to PVP-I during phase I (PVP-I group) and 1188 ones were born to mothers exposed to chlorhexidine in phase II (CHL group); 6.56% of the PVP-I group and 1.91% of the CHL group were recalled later during screening (p < 0.001). The median TSH level was significantly higher in the PVP-I group compared to the CHL group (1.35 vs. 1.00, p < 0.001). Conclusions: Replacement of iodine-containing anti- septics by iodine-free ones, during delivery resulted in a significant reduction in the recall rate of the Iranian screening program for CH. Keywords: congenital hypothyroidism; endocrinology- pediatric; iodine; thyroid function. Introduction First begun in Quebec in 1972, the congenital hypothy- roidism (CH) screening program is today being conducted in most countries. Recall rate is an index for evaluat- ing a screening program, the higher the recall rate, the more the screening costs, because of the further inves- tigations involved. A high recall rate increases the fre- quency of false positive cases at screening and induces unnecessary psychological stress in many families [1], affecting thereby the long-term mother and neonate relationship [2]. The CH screening program conducted in Iran has been scaled up from 2005, facilitating the detection of many transient and permanent cases. Although the inci- dence of CH is about 1 per 1000 live births in Iran [3], the recall rate (approx. 3%–4%) is much above the accept- able range for this program, indicating that permanent CH is finally diagnosed (after 3 years treatment) just in one out of 30–40 recalled cases. This is in sharp contrast to the reported recall rate for CH in other countries, i.e. about 0.05% in US, 0.35% in Australia, 0.28%–0.29% in Hungary, 1%–2% in Turkey and 3.3% in Estonia. The high recall rate in Iran is partially be due to the lower thyroid stimulating hormone (TSH) cut-off point. However, studies have also highlighted the fact that some cases of CH are missed with a higher TSH cut-off value [4, 5]. The threshold of TSH in current screening for CH in Iran is 5 mU/L. Among the different methods of neonate screen- ing, Iran has selected the protocol of CH screening with the heel prick test and TSH, for which there is no defined cut-off point. Each country should start screening with a conservative cut-off point and collect enough data to make *Corresponding author: Mohammad Movahedinia, Shaheed Beheshti University of Medical Sciences, Velenjak St., Shahid Chamran Highway, Tehran 193954719, Iran, E-mail: pudo_72@yahoo.com. http://orcid.org/0000-0001-7889-8015 Majid Valizadeh and Ladan Mehran: Shaheed Beheshti University of Medical Sciences, Research Institute for Endocrine Sciences, Tehran, Iran Farzaneh Moezzi and Zohreh Khavassi: Zanjan University of Medical Sciences, Mosavi Hospital Zanjan, Zanjan, Iran Seideh Mazloomzadeh: Zanjan University of Medical Sciences, Department of Public Health Zanjan, Zanjan, Iran Brought to you by | Lund University Libraries Authenticated Download Date | 9/3/17 4:59 AM