Is there a link between Holt-Oram Syndrome and 'Mardini-Nyhan' association? - need for further research.

To the Editor: We report a case of Mardini-Nyhan association (1–4). Our patient was a preterm (34weeks gestation), small for gestational age, Omani, female neonate (birth weight 1150 g) born to non-consanguineous, elderly parents. She developed respiratory distress 48 h after birth. Physical examination revealed growth retardation, dysmorphic features and a small right thumb; tachypnea, chest retractions, diminished right chest movements and a complete absence of breath sounds on the right side. Heart sounds were heard on the right side with grade two ejection systolic murmur and a widely split second heart sound. Complete blood count, serum chemistry, arterial blood gas analysis and karyotype were normal. A chest radiograph showed total opacification of right hemithorax and herniation of part of the left lung into the right side with compensatory emphysema of the left lung. A color Doppler echocardiogram showed situs solitus, dextraposition and an atrial septal defect (ASD). A computed tomography scan revealed complete agenesis of the right lung with absent main bronchus and vascular structures on the right side (Figure 1). The neonate developed serratia sepsis on the eighth postnatal day, which was managed with broad spectrum antimicrobials and short-term respiratory support. When reviewed at 2 months of age, she was thriving on breast feeds and weighed 2.2 kg and later 5 kg at 6 months of age. Subsequently, her growth and development faltered and she had two episodes of severe bronchiolitis from which she recovered. At 15 months of age, she was brought with a severe episode of respiratory distress due to pneumonia in the left lung and progressive pulmonary hypertension and she succumbed in the emergency room. Mardini and Nyhan (1985) (1) reported four unrelated neonates, all born to consanguineous parents, with lung agenesis and other associated congenital anomalies. A triad of defects, namely unilateral (partial or complete) lung agenesis, ASD and ipsilateral thumb anomalies was observed common to the three female neonates. Subsequently, Hastings et al. (2) reported three neonates, born to non-consanguineous Caucasian parents, with an association of findings similar to that in the Mardini-Nyhan (1) study. They coined a new acronym for this association: LACHT (Lung Agenesis, Congenital Heart, and Thumb Anomalies). Atik et al. (3) reported a similar Fig. 1. CT scan showing complete agenesis of right lung.