Scrotoschisis in a neonate with meconium peritonitis and periorchitis

1 Introduction

Scrotoschisis, the extrusion of the unilateral orbilateral testes through a scrotal defect in a neonate, is hypothesized to occur secondary to meconium peritonitis. Meconium peritonitis occurs with prenatal rupture of the bowel, leading to meconium spillage into the peritoneal cavity. Embryologically, passage of meconium from the peritoneum into the scrotum occurs via the patent processus vaginalis, causing meconium periorchitis. It is hypothesized that meconium in the scrotum leads to inflammation and rupture of the scrotum, permitting extrusion of the testis. Bowel perforations leading to meconium peritonitis most commonly resolve spontaneously before delivery, and in the absence of meconium periorchitis and/or scrotoschisis, the only evidence of a history of meconium peritonitis may be incidental discovery of calcifications on abdominal radiograph [1].

We present the case of an infant born with scrotoschisis, meconium periorchitis and peritonitis. To our knowledge, this is the 23rd case of documented scrotoschisis [2–23], the fifth case with associated meconium periorchitis [2–5], and the second case with meconium peritonitis confirmed via exploratorylaparotomy [4].

2 Case report

The infant’s mother is a 38-year-old African American, gravida 3 abortus 2, female who received routine prenatal care with no abnormalities diagnosed prenatally. The pregnancy was complicated by maternal history of herpes simplex virus treated with Valtrex, cerclage placement at 13 weeks, and preterm premature rupture of membranes treated with a single dose of ampicillin prior to delivery. The 2770 kg infant was delivered vaginally without complications at 34 weeks.

On initial examination, a scrotal defect was noted with exposure of the left testicular tissue and spermatic cord, which appeared to be chronically inflamed with fibrinous exudate (Fig. 1). The scrotal defect did not appear acute, with necrotic changes of the edges of the defect. The right scrotum was intact with noted hydrocele and palpable testis, and normal penile structures were noted when retracted. No additional anomalies were noted on initial exam.

On operative exploration on day of life one, inspection of the right hemiscrotum through the thin, transparent scrotal septum revealed particulate debris in the large fluid collection. The scrotal septum was opened and a large amount of pale green, thick fluid consistent with old meconium was drained. The right testis was inflamed, but appeared viable and appropriately anchored in the scrotum. The scrotal septum was subsequently reapproximated. Left orchiopexy was performed and the scrotal defect closed. The infant passed normal-appearing meconium in the operating room (OR). Given the infant’s benign clinical course, and no evidence of free air on preoperative radiographs, it was elected not to explore the abdomen.

A post-operative abdominal radiograph demonstrated new free air overlying the liver, and the infant emergently returned to the OR for exploratory laparotomy also on day of life one, which showed diffuse greenish staining of the mesentery consistent with prior meconium peritonitis. There was no evidence of succus or enteric contents, and no intestinal perforations were identified.

Cystic Fibrosis (CF) was suspected, but there was no family history of the disease. All three newborn screens showed elevated immunoreactive trypsinogen (IRT). The CF 97 mutations test reported no variant detected. Sweat testing at 11 weeks of life was negative.

3 Discussion

There is mounting evidence supporting the hypothesis that scrotoschisis occurs secondary to meconium peritonitis and periorchitis. We have described what we believe to be the fifth case of scrotoschisis with associated meconium periorchitis. In what follows, we review the previous cases and discuss our case in this context.

Of the 22 previously reported cases of scrotoschisis, only four described an association with meconium peritonitis or periorchitis. However, nearly all report findings that could be consistent with meconium exposure of the testis, spermatic cord, and/or scrotum (Table 1).

Similar to previously described cases, our patient presented with fibrinous exudate surrounding the extruded testicle with associated inflammation. Meconium periorchitis was not immediately apparent, but the diagnosis was confirmed on exploration of the contralateral hemiscrotum and abdominal cavity, and was further supported by the presence of free air and calcifications on postoperative radiographs. We hypothesize that air was introduced into the abdomen during exploration via the persistently patent processus vaginalis that permitted the initial meconium periorchitis. Had the right hemiscrotum not been opened, it is possible that a scrotal mass would have developed with later spontaneous resolution, as originally described by Berdon et al. [24].

Cystic Fibrosis was suspected following the diagnosis of meconium peritonitis and the identification of abdominal calcifications on radiograph. However, pertinent screening and diagnostic tests were within normal limits. Further, the occurrence of CF in babies with an elevated IRT but no CFTR gene mutation is rare, and in one study only 18 out of 8442 babies had CF [25]. However, the possibility of a CF variant cannot be excluded in our infant given the clinical presentation,and further follow up sweat testing at six months is recommended.

Interestingly, there are many more documented cases of meconium periorchitis and peritonitis than there are documented cases of scrotoschisis [26]. What differentiates cases with and without scrotal defects is unknown. We might postulate that cases with scrotal defects simply reach an inflammation and/or pressure threshold as meconium accumulates in the scrotal sac that leads to rupture in utero. However, we cannot overlook the possibility that other factors, such as structural weakness, may play a role. For example, Togami et al. suggested that scrotoschisis is associated with non-development of cremasteric muscles in the scrotum at the site of the defect [15]. In order to better elucidate the pathophysiology, future cases should aim to biopsy and histologically examine the scrotum at the site of the defect prior to closure.

Short-term outcomes in infants presenting with scrotoschisis are generally excellent except for in rare cases involving testicular torsion. However, long-term outcomes for scrotoschisis have not been reported, limited by low incidence and possible underreporting. In the infant we have presented, viability of the left testis was undetermined at the time of discharge. Repeating a sweat test at six months of life will help to further elucidate a possible relationship to a CF diagnosis.

Disclosure statements

All authors: No reported conflicts or disclosures.