Neonate With a Scrotal Swelling

A term neonate with bilateral scrotal swelling was noted immediately following delivery.Born to a 23-year-old primigravida woman with benign prenatal screens.Nonconsanguineous marriage, spontaneous conception.Fetal survey at 19 2/7 weeks’ gestation: normal anatomy.Fetal ultrasonography at 34 3/7 weeks’ gestation: normal anatomy with normal Doppler flow and amniotic fluid index.Estimated gestational age: 37 3/7 weeks.Spontaneous vaginal delivery: thick meconium-stained amniotic fluid, neonate cries immediately after birth.Apgar score: 8 and 9 at 1 and 5 minutes, respectively.Soon after birth, the infant’s scrotal sac was noted to be swollen, but given that the infant was hemodynamically stable, the infant was transferred to the postpartum room. In the nursery, the infant was breastfeeding appropriately with a normal urine and stool pattern.Two days after birth, the infant was transferred to the neonatal intensive care unit after the scrotal sac was noted to be increasing in size.Heart rate: 140 beats/min.Respiratory rate: 52 breaths/min.Blood pressure: 64/44(50) mm Hg.Oxygen saturation: 99% in room air.Temperature: 36.7°C (98.1°F)Birth weight: 2860 g (37th centile), Length: 46cm (13th centile), HC: 32.5 cm (23rd centile).Head: normocephalic: normal, open, flat fontanelles.Face: symmetric face without evidence of any dysmorphism.Eye: no cataracts, chorioretinitis.Oral cavity: pink mucosae, intact palate, normal sucking and rooting reflex.Lungs: clear, equal breath sounds; no respiratory distress.Cardiovascular: normal heart sounds; regular rate and rhythm; no murmur, no gallop.Abdomen: soft, nontender; normal bowel sounds; no hepatosplenomegaly.Genitourinary (Figure 1): Swelling present over left inguinal region with gross scrotal swelling measuring 8 cm × 6 cm × 5 cm with greenish-blackish skin discoloration. Bilateral scrotal swelling is soft, nontender with no erythema, and able to be transilluminated. Bilateral testes are palpable, soft in consistency with the left testis undescended, and nonretractile at the lower inguinal ring without tenderness. A buried penis is also present with a stretched penile length of 2.5cm and shifted to the right side. Urethral opening is normal.Skin: no icterus, birthmarks, or other rashes.Skeletal: spine appears normal.Neurologic: symmetric Moro reflex; normal strength and tone.A stable term infant with bilateral scrotal swelling with left greater than right.Congenital hydrocoelesInguinal herniasMeconium periorchitisTesticular teratomaThe neonate undergoes the following investigations: Complete blood cell count with differential: normal.Blood culture: no growth.Maternal and neonatal serum immunoglobulin G and immunoglobulin M testing for toxoplasmosis, syphilis, rubella, cytomegalovirus, and herpes simplex virus: all normal.Abdominal radiograph: bilateral calcifications over the scrotal region are noted.Scrotal ultrasonography: large fluid-filled collection with calcifications seen in the extratesticular region in both scrotal sacs (Figure 2A); both testes are located at the root of the sac and appear normal in size with normal Doppler flow.Abdominal ultrasonography: free fluid is seen in the left paracolic gutter with internally altered echotexture (attributed to multiple tiny calcificaitons) and septation. One calcification is noted surrounding the capsule of the liver anteriorly (Figure 2B).Computed tomography of the abdomen and pelvis: a soft tissue lesion is seen in the left scrotal sac measuring, 3.9 cm × 4.4 cm with multiple tiny calcific foci within (Figure 3A). The left scrotal wall is thickened and shows calcifications with bilateral hydroceles. Bilateral hydroceles are noted with the left side being larger than the right. A calcific foci is also seen along the subdiaphragmatic and liver capsule surface (Figure 3B).Skull ultrasonography: normal.Serum immunoreactive trypsinogen assay: negative.Meconium periorchitis secondary to meconium peritonitis.The neonate remains hemodynamically stable. He has a gradual reduction in the scrotal swelling without any compromise to the testicular vascularity. The patient is discharged at 10 days of age with follow-up arranged with the neonatology outpatient clinic and pediatric surgery.Meconium periorchitis (MPO) is an uncommon condition that can occur as a complication of meconium peritonitis (MP). MPO has a reported incidence of 1 per 35 000 live births.1 MP is classified into 3 types depending on the antenatal ultrasonography findings2: Type I: large meconium ascites.Type II: large pseudocyst.Type III: intra-abdominal calcifications, small meconium ascites, and/or a shrinking pseudocyst. The neonate described in this case has findings most consistent with type III MP.MP is caused by intrauterine bowel perforation and exudation of meconium into the peritoneal cavity, which leads to chemical peritonitis. In an attempt to seal the perforation, adhesions are formed around the perforation, creating a pseudocyst. In the absence of pseudocyst formation, the continuous oozing of meconium into the peritoneal cavity results in chemical peritonitis and ascites.3 Ultrasonography in the antenatal period is a poor diagnostic modality for MP with a low sensitivity rate of 22%.4Favorito et al described 3 possible mechanisms leading to meconium entry into the scrotal sac in patients with MPO: Fetal intestinal perforation leading to meconium spilling directly into the processus vaginalis and the developing scrotum.Fetal intestinal perforation near an undescended testis followed by adherence of the perforated segment to the testis during its descent from the abdominal cavity into the scrotum.Necrosis or perforation of a strangulated portion of the fetal intestine leading to spillage of meconium into the processus vaginalis and then the scrotum.3The presence of meconium in the scrotal sac leads to an inflammatory reaction, which leads to a mass-like scrotal lesion. The consistency and appearance of meconium in the scrotum evolve over time with the extratesticular mass being soft at birth and subsequently becoming firmer over the next few weeks as the meconium calcifies. The patient’s age at the time of diagnosis of the associated mass varies from 1 month to 5 years.5The most common initial event that causes MP before the development of MPO is small bowel atresia (primarily ileal atresia), which is responsible for more than 50% of cases; cystic fibrosis accounts for nearly 10% of cases of MP.6 The possibility of underlying cystic fibrosis should always be evaluated.As in the neonate described in this case, patients with MPO have regression in the testicular swelling without any compromise to the testicular vascularity, corresponding to the benign nature of the lesion. Affected patients can be managed conservatively. In the case of continued increased scrotal swelling size with or without compromise to the testicular vascularity, surgical intervention may be needed. Reports of MPO with long-term follow-up suggest normally functioning testes with spontaneous complete resolution of the associated mass in 1 to 5 years.7 These findings emphasize the importance of avoiding orchidectomy in neonates with MPO.Other diagnoses to consider in this patient with peritoneal calcifications include infections such as congenital cytomegalovirus and congenital toxoplasmosis. These diagnoses were ruled out in the neonate in this case because of absent intracranial calcifications and negative infectious testing. Inguinal hernias often present as nontender easily reducible swelling and seldom have associated fluid collections or calcifications.8 An infant with a testicular teratoma presents with a firm mass with ultrasonography that demonstrates multiseptated cystic lesions with accompanying hypervascularity on Doppler flow.8 Testicular torsion and traumatic hydrocele are present as neonatal surgical emergencies with discoloration and tenderness being the predominant symptom and Doppler ultrasonography confirming decreased perfusion.8MPO is an uncommon entity that consists of mass-like scrotal lesions caused by in-utero passage of meconium into the scrotal sac.Scrotal calcifications seen on ultrasonography are the hallmark of this benign condition.Differentiating MPO from other concerning causes of a paratesticular mass is important and can avoid an unnecessary orchiectomy.