Diprosopus, or craniofacial duplication, is an extremely rare congenital malformation, representing only 0.4% of conjoined twins with an estimated prevalence of 1 in 15 million births. Fewer than 40 cases have been reported worldwide. We describe a case of partial craniofacial duplication in a child from rural Ethiopia, highlighting the challenges of delayed diagnosis and management in a resource-limited setting. A 7-year-old girl presented with a congenital mandibular mass that had remained untreated since birth due to a lack of antenatal care (ANC) and delayed health-seeking. Examination revealed a pedunculated soft tissue lesion containing duplicated rudimentary facial elements, including tooth-like structures and lip-like tissue. Laboratory investigations were normal, and skull radiography showed no bony abnormalities. Advanced imaging was not feasible. The mass was excised surgically, and gross and histopathological evaluation confirmed partial craniofacial duplication. Postoperative recovery was uneventful, with improved psychosocial outcomes. Unlike complete diprosopus, which is typically incompatible with life, partial forms may permit long-term survival. The embryopathogenesis remains debated, with proposed mechanisms including incomplete embryonic disc division and neural crest duplication. While management in well-resourced settings is often facilitated by advanced imaging and multidisciplinary planning, this case demonstrates that direct surgical excision can achieve favorable outcomes even where resources are limited. This rare case contributes to the limited literature on diprosopus and underscores the importance of strengthening ANC, anomaly screening, and community awareness. Timely surgical intervention, even in low-resource environments, can restore function and enhance psychosocial outcomes.

Congenital malformations, including cephalic anomalies such as diprosopia and dicephalia, represent rare but significant developmental abnormalities in humans and animals. While these conditions are primarily attributed to incomplete embryonic splitting, their genetic origins in domestic animals remain poorly understood. This study presents a detailed molecular and anatomical investigation of three cases of cephalic malformations in ruminants: two Holstein-Friesian calves and one Mediterranean Italian River Buffalo. Anatomical analyses classified the malformations as diprosopus in two cases and dicephalic in one. Notably, this is the first reported case of dicephalia in a female Mediterranean Italian River Buffalo. Molecular analysis using microsatellite markers and sex-linked genes (AMELX/Y and SRY) confirmed the monozygotic origin and the female sex of all cases, with identical genotypes detected in both heads of each calf.

Diprosopus is an exceedingly rare craniomaxillofacial dysmorphosis that is considered a subgroup of conjoined twins. This phenotype encompasses a broad spectrum of duplications ranging from partial structures to complete dicephalus. The embryogenesis and mechanism of disease are not well understood. The objective of this investigation was to describe a case of partial dentofacial duplication and to discuss the possible etiology with novel genetic insights thereof. A newborn Kazakh boy was referred to the First Affiliated Hospital of Xinjiang Medical University because of a maxillary mass detected on prenatal imaging. Physical examination revealed a unilateral cleft lip and a soft lump around 2.5 cm in diameter with the appearance of an accessory upper lip. He underwent two surgical procedures at 11 months and 4 years of age for definitive treatment. He demonstrated favorable recovery outcomes, maintaining normal speech and oral intake capabilities during long-term follow-up. Our preliminary findings and comprehensive literature review suggest that mutations in the PAX7 gene could contribute to the pathogenesis of craniofacial duplication. This hypothesis establishes a previously unrecognized association between specific genetic alterations and the clinical manifestations of this condition, potentially offering a molecular foundation for prenatal diagnostic approaches. The present case provides more profound insights into the disease mechanisms compared to prior reports. Further validation through basic scientific investigations and clinical studies, incorporating comprehensive genetic analyses, will be essential to substantiate this proposed mechanism.

Diprosopus is one of the rarest anomalies. It typically manifests as bilateral alterations and often involves anomalies within the cranial structures. In this report, we present a case of a fetus with diprosopus diagnosed prenatally. Along with reviewing relevant literature on prenatal ultrasound diagnosis of diprosopus, we aim to raise awareness of its ultrasound characteristics. We report a case of craniofacial and intracranial abnormalities detected during a 26-week ultrasound examination. Two-dimensional ultrasound (2D ultrasound) demonstrates significant increases in head circumference, widening of the interocular distance, and abnormal echo patterns in the facial structure. Three-dimensional ultrasound (3D ultrasound) revealed the presence of three eye sockets (the lateral eye sockets contained eyeballs, while the central region exhibited fusion without visible eyeballs), two noses, and two mouths, with no abnormalities observed in other areas. The ultrasound findings suggested diprosopus. Following risk counseling at the prenatal diagnosis center, the pregnant woman decided to induce labor. The newborn passed away thirty minutes after delivery. The facial features of the newborn were consistent with the 3D ultrasound imaging, and the appearance of the trunk and limbs was normal. Both CT and MRI scans confirmed the diagnosis of diprosopus. The prenatal 2D ultrasound revealed intracranial and facial abnormalities in the fetus. 3D ultrasound imaging clearly displayed the facial duplication anomalies, highlighting the advantages of 3D ultrasound in diagnosing diprosopus. We hope to raise awareness of this rare condition and provide insights into prenatal ultrasound diagnosis through this case.

A case of diprosopia anomaly in a blue shark (Prionace glauca) embryo from the South Atlantic Ocean is described. A detailed morphological description of internal organs was provided. The sample came from a pregnant female caught near Trindade Island (19°29'30"S, 028°20'00"W) in Southeast Brazil, with three normal embryos and one with external morphological abnormalities. The anomalous embryo was a male, with deformities in the skull and curvature of the spinal column twisted from the end of the first dorsal fin to the end of the caudal fin in a counterclockwise direction. Furthermore, two faces were observed, the right one with few alterations, while the left one was fused to it, with deformations in the eyes, mouth and nostril. The stomach was the only organ to show alteration in its shape, macroscopically. Organs of the digestive tract, renal structures and rectal gland was analyzed microscopically, and no alteration were observed in the samples. This is the first description of the internal organ of a specimen with diprosopia. These results suggest that, in addition to other factors, the survival of the embryo could be related to their ability to feed and escape predators in case to survive birth.