Pyle disease (metaphyseal dysplasia) presenting in two adult sisters

Abstract

Pyle's disease is an extremely rare skeletal disorder characterized by a benign course and an autosomal recessive genetic pattern of inheritance. Its causal mutation is still unknown. In the medical literature, fewer than 30 cases have been described to date. We report the case of two female siblings, daughters of consanguineous parents, referred to the radiology department complaining of genu valgum. Laboratory tests showed no other relevant findings. Conventional radiography plain films revealed Erlenmeyer flask deformity in bilateral femorotibial metaphyses, metaphyseal flaring of long bones, and mild sclerosis of the skull base. The clinicoradiological dissociation, along with the characteristic imaging findings, was consistent with the diagnosis of Pyle's disease. Intervention is not required in most cases, but orthopedic treatment may be required for genu valgum or fractures. Therefore, these cases emphasize the pivotal role conventional radiography plays in the correct diagnosis of this rare entity, allowing for appropriate genetic counseling.

Pyle’s Disease

“…6 Diego et al also reported case of two female siblings, daughters of consanguineous parents. 7 Laboratory tests showed no other relevant findings as is in our case.…”

Rare case of Pyle’s metaphyseal dysplasia presenting in an adult

“…Pyle's metaphyseal dysplasia (PMD) is an extremely uncommon and rare genetic skeletal disorder, with fewer than 30 cases reported worldwide, characterized by a benign course of irregular development of long bones, and an autosomal recessive genetic pattern of inheritance [1][2][3]. This disease was named after the American orthopedic surgeon, Edwin Pyle, who first reported the disease in 1931.…”

“…Other less marked changes may be seen in other distal long bones, distal metacarpals and proximal phalanges. Spinal involvement varies from no changes at all to a moderate platyspondyly or biconcave lens appearance of the vertebral bodies [1,4]. Homozygous mutations in secreted frizzled-related protein 4 (SFRP4) gene have been related to this condition.…”

Hereditary Metabolic Bone Diseases: A Review of Pathogenesis, Diagnosis and Management

“…Broadening of proximal two-third humeral bones and distal two-thirds radial and ulnar bones can also be observed. Other clinical presentations include metaphyseal fracture, bilateral knee enlargement, broadening proximal phalanges and distal metacarpal bones, dental abnormalities and jaw protrusion (prognathism) [ 55 ].…”

“…Given the benign nature of the disease, most cases of Pyle disease do not require intervention. However, orthopedic treatment may be required for significant genu valgum or metaphyseal fractures [ 55 ].…”