Critical Review: Neonatal Ascites Diagnosis and Management

Introduction

The article "An Unusual Cause of Neonatal Ascites" by Espírito Santo et al. (2017) is a case study presentation on fetal ascites, tracing the condition from diagnosis during the fetal period through clinical management in infancy. The article presents a clinical case of neonatal ascites following maternal refractory hypertension in a 30-year-old primigravida. Investigations began with the mother and included a blood type test, infectious serology, and indirect Coombs test. The central clinical problem is the management of neonatal ascites — from initial diagnosis based on maternal signs through to post-birth management if ascites persists.

This paper is a critical review of that article. The review explains the importance of sonography in the diagnosis of ascites, provides background on the condition and its epidemiology, examines its clinical implications, and concludes with a personal opinion.

Importance of Sonography in Diagnosis

Sonography (ultrasound) is critically important in the diagnosis of ascites, including during the fetal period. The use of ultrasound is so central to ascites investigations that clinicians routinely incorporate it into diagnostic guidelines (Ennis et al., 2014). Ultrasound is preferred because it allows for rapid detection of ascites even when fluid pockets are small. Once fluid pockets have been identified, ultrasound is used again to locate the thinnest regions of the abdominal wall for fluid evacuation. Evacuation is performed with a needle, and selecting an appropriate area ensures that a needle of suitable length can traverse the abdominal wall effectively.

Because ascites causes edema and consequent thickening of the abdominal wall, identifying a suitable puncture region is essential for safe paracentesis. Ultrasound also enables clinicians to identify vascular structures within the tissue — particularly collateral structures and epigastric vessels — so that they can be avoided during the procedure (Ennis et al., 2014). Finally, as demonstrated in the case study, ascites can be diagnosed at the fetal stage when a maternal health condition predisposes the fetus to the condition. Ultrasound remains the most effective and clinically safe method available for fetal detection of this condition.

Pertinent Statistical Data on Ascites

Ascites results from conditions that directly involve the peritoneum — such as infection or malignancy — or from diseases remote to the peritoneum, including heart failure, liver disease, and hypoproteinaemia. Isolated ascites is uncommon. In the Western world, cirrhosis accounts for approximately 75% of ascites cases, making it the most common cause. The second most common cause is peritoneal malignancy at 12%, followed by cardiac failure at 5%, and peritoneal tuberculosis at 2% (Runyon, 2013; Ennis et al., 2014).

Patients who develop ascites have approximately an 85% chance of surviving one year. However, this drops to 25% once ascites has progressed to refractory ascites, hyponatraemia, or hepatorenal syndrome (HRS). Analysis of normal ascitic fluid shows it contains fewer than 500 leukocytes/mL and fewer than 250 polymorphonuclear leukocytes per mL. Although any inflammation can raise the white blood cell count, counts greater than 350/µL suggest infection (Runyon, 2013). Available treatments do not produce significant improvements in survival; however, treatment is important because it improves quality of life.

References

Ennis, J., Schultz, G., Perera, P., Williams, S., Gharahbaghian, L., & Mandavia, D. (2014). Ultrasound for detection of ascites and for guidance of the paracentesis procedure: Technique and review of the literature. International Journal of Clinical Medicine, 5(20), 1277.

Espírito Santo, R., Martins, R., Valente, S., & Saldanha, J. (2017). An unusual cause of neonatal ascites. BMJ Case Reports, 2017, bcr-2017.

Runyon, B. A. (2013). Introduction to the revised American Association for the Study of Liver Diseases Practice Guideline management of adult patients with ascites due to cirrhosis 2012. Hepatology, 57(4), 1651–1653.