Infantile cortical hyperostosis

Clinical History

At 9 months of age the child presented with a history of irrtability and soft tissue and bony swelling of 3 month's duration. There were no systemic symptoms. Clinical examination showed soft tissue and bony swelling over the mandible, clavicle and tibia on the left side. Haematological investigations were normal. X-rays showed cortical thickening of the mandible, clavicle, ribs and tibia on the left side.

Imaging Findings

The patient's mother brought the 9-month-old infant to the orthopaedic clinic complaining of persistent irritability and poor feeding over the previous 3 months. On further questioning she revealed that she had noticed that the left leg was thicker than the right. There was no history suggestive of fever or loss of weight. There was no similar history in the family. Clinical examination showed an irritable child with normal temperature and pulse. General examination did not reveal any anaemia or lymphadenopathy. Examination of the right leg showed that there was a uniform increase in the thickness of the right leg compared to the left. The skin was stretched. No dilated veins, scars or sinuses were noted. There was no local rise in temperature, no redness and no tenderness. No regional lymphadenopathy was noted. The mandible, left clavicle and ribs on the left side were thickened. X-rays showed uniform a periosteal reaction in the tibia from metaphysis to metaphysis. The fibula was normal. Chest X-ray and blood investigations were normal.

The patient was managed conservatively, reassuring his mother. At follow-up after 3 months the mother complained that although the child was better than before, the leg swelling seemed to be getting worse. The child continued to be afebrile. Careful clinical palpation of the leg showed a further increase in the girth compared with the last examination. The X-rays were repeated. The mother was reassured and was sent home.

Discussion

Infantile cortical hyperostosis or Caffey's disease was first described by Caffey and Silvermann in 1945. It constitutes a triad of irritability, soft tissue swelling and cortical thickening of underlying bone with no sex or race predilection.

The origin is unknown, but numerous reports of familial occurrence suggests a probable hereditary origin with autosomal dominance with incomplete penetrance (1). It involves a defect of the periosteal arterioles, and infection and a dietary role have been postulated.

Pathologically there is marked inflammation involving the periosteum and the surrounding soft tissues. This leaves the underlying periosteum thickened, followed by lamellar bone formation. Experimental studies suggest hypoxia as a causative agent for reactive hyperostosis. Bones involved, in order of frequency, are mandible, ulna, tibia, clavicles, scapulae and ribs. Rarely the skull bones are involved, and the bones of the hand or vertebrae are never involved. Commonly more than one bone is affected. It commonly occurs around the 5th month of postnatal life, although a perinatal lethal type (2) and a late-onset type (3) have also been described.

Clinical features are hyperirritability and a local mass, often over the mandible. The swelling is sudden in appearance, firm and may be tender initially. There is no local heat or redness. Blood investigations are normal. Radiographic appearances show abundant new bone formation resulting in an increase in diameter of the bone. Rarely intramedullary lytic lesions have been reported (4). Differential diagnosis includes Ewing's sarcoma, chronic osteomyelitis, and hypervitaminosis A. Biopsy is rarely necessary to confirm diagnosis. Treatment is usually reassurance with steroids for acute presentation. Use of indomethacin has been mentioned (5). Reactivation of the lesions has also been reported.

Differential Diagnosis List

Final Diagnosis

Infantile cortical hyperostosis, Caffey's disease

URL:	https://www.eurorad.org/case/1827
DOI:	10.1594/EURORAD/CASE.1827
ISSN:	1563-4086