Recurrent Idiopathic Nonimmune Hydrops Fetalis: A Case Report

Military Medicine, Oct 2006 by Ergur, Ali Rustu

A recurrent idiopathic nonimmune hydrops fetalis case in two subsequent pregnancies was observed in a woman with no child. In both pregnancies, all the detailed analysis, including a high level of ultrasonography, amniocentesis, serologic evaluation, routine blood work, hemoglobin electrophoresis, and glucose 6-phosphate/dehydrogenase level and postdelivery autopsy, was done, and after no clue of etiologic agent, pregnancy termination was applied for both. This case report illustrates the importance of recurrence of nonimmune hydrops fetalis in the absence of any etiology. Mostly, it is hard to establish an etiologic diagnosis for adequate management of subsequent pregnancies.

Introduction

Nonimmune hydrops fetalls (NIHF) is a condition of hydropic fetus due to causes other than Rh isoimmunization Including mainly cardiovascular, hematologic, neoplastic, chromosomal, hereditary, or Infectious disorders.1,2 Mostly, it is hard to ascertain the underlying reason in fetuses with NIHF, and in those with specific etiologies, treatment options are very limited. The frequency of hydrops is approximately 1:2000 to 1:3000 with 85 to 90% contribution of nonimmune causes; prognosis is poor even in fetuses with a detected underlying reason.3 The contribution of nonimmune hydrops to the total perinatal mortality rate has increased from 0.1% to 3% in the last decade.4

The etiology of some NIHF cases remains unclear even after thorough Investigation.5 The incidence of "idiopathic cases" of NIHF has not changed in the last decade and is approximately 20%.6,7 On the other hand, the recurrence of idiopathic NIHF cases is very seldom and is sometimes attributed to genetic factors.6 To date, eight case reports5,8-14 for recurrent NIHF have been reported and only two of them had no etiologlc factor.8,9

In this case report, we present a patient with two losses due to idiopathic NIHF in a very short time interval. Also, we wanted to evaluate the realities behind idiopathic NIHF, whether they are real idiopathic cases or whether they have etiologies that we cannot find.

Case Report

A 23-year-old woman (T.Y.), gravida one, para zero, was referred to our department due to the detection of fetal hydropic condition by another obstetrician. We performed a detailed ultrasound examination and detected a fetus with severe generalized edema, ascltes, hydrothorax, and hydropic skull (Fig. 1). The blometric evaluation of the affected fetus was in concordance with its age of gestation as 18 weeks of pregnancy. The detailed evaluation did not give us any clue of congenital malformations except an echogenic intracardiac focus with 9.3 mm of nuchal translucency. The placental thickness and the amount of amniotic fluid were normal. The maternal blood group was O Rh positive and the indirect Coombs was negative. The serologic evaluation of the pregnant woman for toxoplasmosis, rubella, cytomegalovirus, herpes simplex, syphilis, and parvovirus B-19 showed us no infectious serum titers. All other routine analysis, including hemoglobin electrophoresis and glucose 6-phosphatase level, was in normal limits with a hemoglobin concentration of 11.2 g/dL and 34% of hematocrit. Thereafter, the fetal karyotype was evaluated to detect the chromosomal causes of the hydrops according to the data that chromosomal abnormalities account for two-thirds of hydrops etiologies, and the result was normal karyotype, 46 XY. The parents were asked about genetic disorders, especially the clues of metabolic ones in their family, and no special condition to explain the fetal hydrops was found. Therefore, no analysis was performed related to specific autosomal recessive genes. The pregnancy was terminated with oral and vaginal misoprostol application 1 week later; after delivery, macroscopic evaluation of the fetus revealed no external pathology except generalized hydropic condition. The fetal hematologic evaluation, including whole blood analysis and hemoglobin electrophoresis, was in the normal limits. Also, the autopsy of the fetus confirmed our findings with no sign of congenital pathology that might be the cause of hydrops but skin and placental edema, ascites, and pleural and pericardial effusions. The bulky placenta was pale and friable. The umbilical cord was also edematous. The microscopic examination revealed edematous changes mostly affecting the central parts of the villi and Hafbauer cells were striking in some areas. Neither neoplastic cellular infiltration nor abnormal vascular organization was present. Accumulation of metabolites within trophoblastic cells, resulting in cytoplasmic changes and/or thickening of the trophoblastic layer suggesting any of the known genetic metabolic disorders, was not seen.

Ten months from the termination of the first pregnancy, the patient became pregnant again and had the same hydropic fetal signs of a new complicated 20 weeks of pregnancy. One more time, all of the detailed analysis, including high level of ultrasonography, karyotyping, serologic evaluation, and postdelivery autopsy, was done. This time, the fetus was a chromosomally normal female, 46 XX, and all completed analysis for the etiology again did not give us any clue about the hydrops occurrence. The fetus was delivered by oral and vaginal misoprostol and presented no pathologic finding. We could not find any possible explanation for nonimmune hydrops fetalis conditions in both pregnancies, although complete detailed analyses for etiology detection were performed.