A 4.18kg full-term neonate, who was undergoing phototherapy and was otherwise well, developed localised left-sided abdominal bruising in the inguinal and scrotal area on day four (see Figure 1). 

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The infant had been born by normal delivery with no history of trauma or perinatal asphyxia and had remained in hospital from birth. Haemoglobin, platelets and coagulation studies were normal. An abdominal ultrasound identified a 3.1cm right-sided adrenal haemorrhage (see Figure 2). 

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In neonates the adrenal gland is relatively large and vulnerable to vascular damage. Adrenal haemorrhage may occur in the context of macrosomia traumatic delivery, hypoxia, coagulation disorder, sepsis, and neuroblastoma.^1,2 Blood may track from the perinephric tissues into the peritoneal cavity or the retroperitoneum. In boys this may present as scrotal swelling and discolouration mimicking testicular torsion.^3,4

Adrenal haemorrhage may occur spontaneously in well neonates as illustrated by our case. In an infant with unexplained abdominal bruising, non-accidental injury would also be a differential diagnosis.

References

1. Demirel N, Yağmur Baş A, Zenciroğlu A Taşcı-Yıldız Y. Adrenal bleeding in neonates: report of 37 cases. Turkish J Pediatr. 2011; 53: 43-7 turkishjournalpediatrics.org/uploads/pdf_TJP_870.pdf 
2. Gyurkovits Z, Maróti Á, Rénes L, Németh G, Pál A, Orvos H. Adrenal haemorrhage in term neonates: A retrospective study from the period 2001-2013. J Matern Fetal Neonat Med. 2015; 28 (17): 2062-5. 10.3109/14767058.2014.976550 
3. Adorisio O, Mattei R, Ciardini E Centonze N, Noccioli, B. Neonatal adrenal haemorrhage mimicking an acute scrotum. J Perinatology. 2007;27:130-2  doi:10.1038/sj.jp.7211638
4. Lai LJ, Chen LM, Chu PY, Tseng MH, Chang CC, Lu CW. Neonatal Adrenal Hemorrhage Associated with Scrotal Hematoma: An Unusual Case Report and Literature Review. Pediatr Neonatology. 2012;53(3):210-12 dx.doi.org/10.1016/j.pedneo.2012.04.010

Full author list: Qamar Ali, Consultant Paediatrician, South West Acute Hospital, Enniskillen; Muhammad Azam, Consultant Paediatrician, Wexford General Hospital; Maybelle Wallis, Consultant Paediatrician, Wexford General Hospital; and Richard Deignan, Consultant Radiologist, Wexford General Hospital