Acardius acephalus in a kid

Introduction: Acardius acephalus is a form of monozygous twins in which the parasitic twin is joined by the chorionic or cord vessels to the other twin. Materials and Methods: A malformed fetus, delivered by an adult black Messinese goat, was examined radiologically and grossly. Results: The fetus had only a single pair of limbs. External genitalia were represented by an inhabited scrotum. Radiological examination revealed the presence of morphologically unremarkable hindlimbs and a malformed pelvis. The vertebral column appeared malformed, turned at an angle of 90 and ventrally shifted, with clear morphological anomalies of lumbosacral vertebral bodies. There was an absence of subcutaneous fat and muscular hypoplasia was noted. Omphalocoele and a probable preputial sheath, internally connected to a rudimentary urethro-penile structure leading to the urinary bladder, were detected. The intestine comprised only an ileum, an atretic dilated and blind caecum and a colon. No other abdominal or thoracic organ was detected. Conclusions: On the basis of gross and radiological findings the malformation was classified as acardius acephalus. In human medicine, acardia is a rare and severe abnormality reported as a unique complication of monozygotic twin pregnancies, known as twin-reversed arterial perfusion (TRAP).