Neonatal adrenal haemorrhagic pseudocyst.

JZ Patankar, VP Mali, K Prabhakaran 
 

Correspondence Address:
J Z Patankar

Full Text

Sir,

A seven days old male neonate born to a diabetic mother (mild gestational diabetes) at term after an uncomplicated pregnancy with a birth weight of 3000gms, presented with a left sided flank mass. The neonate was otherwise asymptomatic. Standard laboratory tests were unremarkable. Ultrasound revealed a non-homogenous cystic mass lesion 3.9cm x 3.2cm at the upper pole of left kidney. Spiral un-enhanced computerised tomographic (CT) scan revealed a left renal mass measuring about 5 cm x 4.2cm x 6.5cm.The right kidney was essentially normal. Nuclear scan revealed an area of photopenia seen in the upper pole of the left kidney probably due to tumour as noted previously on the CT scan. This had displaced the left kidney slightly inferiorly. The right kidney had a normal configuration. The provisional diagnosis was made as congenital neuroblastoma. Surgical exploration was decided upon to exclude malignancy. At laparotomy, the right kidney was normal to palpate. Liver was normal. The left kidney showed foetal lobulations. A cystic mass was palpated in close proximity to the upper pole of the left kidney with no plane between the mass and the renal capsule. With a strong suspicion of malignancy, a radical left nephrectomy was done. Postoperative course was uneventful. Final histopathology revealed adrenal haemorrhagic pseudocyst, fetal lobulations of the left kidney with normal renal parenchymal structures.

Adrenal haemorrhage (AH) is not an exceptional event in the newborn. The probable predisposing factors are difficult delivery, foetal hypoxia, thrombocytopenia and coagulation defects. Additional risk factors are maternal diabetes, breech delivery, perinatal asphyxia and neonatal sepsis. The differentiation between neonatal neuroblastoma and adrenal haemorrhage may be very difficult in any individual case. A high index of suspicion is required to make a timely diagnosis of AH.

Clinical and radiological differential diagnosis for a left sided abdominal mass in a newborn may be neonatal adrenal haemorrhage, congenital neuroblastoma and retroperitoneal teratoma. The sonographic appearance of an AH is an echogenic suprarenal mass which is difficult to distinguish from a congenital neuroblastoma. Sonographic differentiation may be very difficult as neonatal neuroblastoma may have a cystic appearance[1] and AH may present as a solid suprarenal mass. Haemorrhage into a congenital neuroblastoma may occur which makes the differentiation between AH and neuroblastoma extremely difficult.[2],[3]

Colour coded Doppler sonography is useful to differentiate between congenital neuroblastoma and AH. In neuroblastoma it shows a network of microscopic vessels that invade the tumour and provide blood supply essential for its growth.[4] This network gives rise to characteristic high velocity Doppler shifts. In contrast to neuroblastoma, AH is characterised by diminished or absent blood flow.

Our case highlights the diagnostic problems that arise when a space-occupying lesion is found near or at the adrenal gland. The absence of signs of bleed (shock, anemia or hemolytic jaundice) cannot be taken as proof that a neoplasm is present. Although surgical exploration has been advised to exclude malignancy, it is imperative to try to make the differentiation by non-operative means, such as repeated ultrasound, CT-scan and fine needle aspiration biopsy. Non-operative management of neonatal AH gives excellent results, whereas too aggressive approach may end in the removal of non-diseased organs.[5]

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