Congenital adrenal hyperplasia (CAH) or Wolff–Parkinson–White (WPW): The difficulties of diagnosing a shocked neonate

Abstract

The acutely unwell and shocked neonate is an important clinical challenge for paediatricians. In general, management involves concurrent resuscitation and investigation of the underlying cause. Although the most common causes of shock in the neonatal period are sepsis and dehydration, there are a wide range of other diagnostic possibilities that should be considered. 1 Here, we present the case of a neonate who presented with shock, hyponatraemia and hyperkalaemia. The diagnostic journey was challenging and instructive. Case StudyA 14-day-old, ex-38/40 male boy born by normal vaginal delivery presented to the emergency department of our hospital with a 3day history of poor feeding and reduced wet nappies.On examination, he looked unwell, with a mottled grey-bronze colouration, cool peripheries and delayed capillary refill time. His heart rate was 140 and regular, respiratory rate 100 and rectal temperature 33.5°C, and on cardiovascular examination, he was noted to have a gallop rhythm and a 2/6 systolic murmur. On abdominal examination, he was noted to have hepatomegaly. The femoral pulses were palpable bilaterally. His scrotum appeared well pigmented (Fig. 1). His genitalia were of normal appearance with both testes present. His weight had increased from a birth weight of 3050 to 3560 g.

The Pathophysiology, Diagnosis, and Management of Wolff–Parkinson–White Syndrome in the Neonate

“…The process's complexity creates a high likelihood for malformations to occur. The APs completely disregard anything distal to the AV node, including the bundle of His, right and left bundle branches, and Purkinje fibers, creating rapid antegrade cardiac conduction from the firing of the SA node straight through the accessory conduction pathway to the ventricles 3,4,7,11,12. A visual comparison of normal cardiac conduction versus WPW conduction is available in Figure 1.…”

“…The fetus may present with intermittent or sustained episodes of SVT, with a ventricular rate greater than 180 beats per minute (bpm) and evidence of asynchronous atrial and ventricular contraction visualized on fetal echocardiogram 4,9,16,18. When the tachyarrhythmia persists for greater than 6 to 12 hours and decreased cardiac stroke volume ensues, the fetus may develop signs of congestive heart failure (CHF), such as hydrops fetalis 12,16,17…”

“…Most neonates present with ambiguous symptoms similar to common diagnoses including anemia, stress, fever, electrolyte abnormalities, sepsis, dehydration, shock, and congenital structural cardiac defects 7,8,23. Supraventricular tachyarrhythmias are almost always present with WPW, but frequently only recognized upon evaluation by a trained medical provider during a routine evaluation or during evaluation of the infant for nonspecific symptoms such as irritability, inconsolable bouts of crying, poor feeding, gastrointestinal symptoms, respiratory distress, cyanosis, and lethargy 6,7,9,12,14,16–18…”

“…The incidence of WPW is likely underestimated due to undiagnosed cases among asymptomatic patients and underreporting due to potential misdiagnosis; however, it remains the most common cause of ventricular preexcitation, with an incidence of 0.1% to 0.31% among the general population and 0.1% to 0.2% among neonates 5,8,10,12–14. A multitude of risk factors exist for the development of WPW, with many genetic risk factors still actively being researched.…”

“…The risk of cardiac arrest and sudden death is rare in the grand clinical picture of a WPW diagnosis; however, it is most prevalent in children who were previously asymptomatic 3,14. Unfortunately, there is no rapid, standardized diagnostic screening for neonatal patients or urgency in neonatology to develop standardized management of WPW as a congenital heart defect, despite the known risk of sudden cardiac death with episodes of hemodynamically unstable SVT 12,17. Implementing a standardized approach for early diagnosis and treatment of WPW is imperative to allow healthcare providers the opportunity to identify the presence of WPW in the neonatal period, provide immediate management and appropriate follow-up postdischarge, and potentially prevent catastrophic outcomes.…”