Pachydermoperiostosis: a rare mimicker of acromegaly

Abstract

Pachydermoperiostosis is a very rare osteoarthrodermopathic disorder whose clinical and radiographic presentations may mimic those of acromegaly. In the evaluation of patients with acromegaloid appearances, pachydermoperiostosis should be considered as a differential diagnosis. In this article, we report a 17-year-old boy who presented with 2-year history of acral enlargement and facial appearance changes associated with joint pain and excessive sweating. He had been investigated extensively for acromegaly, and the final diagnosis was pachydermoperiostosis.Learning pointsThere is a broad range of differential diagnosis for acromegaloid features such as acromegaly, pseudoacromegaly with severe insulin resistance, Marfan’s syndrome, McCune–Albright and a rare condition called pachydermoperiostosis.Once a patient is suspected to have acromegaly, the first step is biochemical testing to confirm the clinical diagnosis, followed by radiologic testing to determine the cause of the excess growth hormone (GH) secretion. The cause is a somatotroph adenoma of the pituitary in over 95 percent of cases.The first step is measurement of a serum insulin-like growth factor 1 (IGF1). A normal serum IGF1 concentration is strong evidence that the patient does not have acromegaly.If the serum IGF1 concentration is high (or equivocal), serum GH should be measured after oral glucose administration. Inadequate suppression of GH after a glucose load confirms the diagnosis of acromegaly.Once the presence of excess GH secretion is confirmed, the next step is pituitary magnetic resonance imaging (MRI).Atypical presentation warrants revision of the diagnosis. This patient presented with clubbing with no gigantism, which is expected in adolescent acromegalics as the growth spurt and epiphyseal plate closure have not taken place yet.

Pacydermoperiostosis Associated With Pigmented Villonodular Synovitis

“…Pachydermoperiostosis is a rare genetic disorder with autosomal dominant or autosomal recessive transmission and variable expression known also as primary hypertrophic osteoarthropathy and TouraineSolente-Gole syndrome [1][2][3]. The proposed mechanism of the disease is the increase of seric levels of Prostaglandin E2 (PGE2) produced by inactivating mutations of Hydroxy-Prostaglandin Dehydrogenase (HGPD) enzyme (responsible for PGE2 degradation) or of SLCO2A1 (a PGE2 transporter) [1,2,4].…”

“…The proposed mechanism of the disease is the increase of seric levels of Prostaglandin E2 (PGE2) produced by inactivating mutations of Hydroxy-Prostaglandin Dehydrogenase (HGPD) enzyme (responsible for PGE2 degradation) or of SLCO2A1 (a PGE2 transporter) [1,2,4]. Increased seric levels of PGE2 are inducing various metabolic modifications of skin, bones, joints and blood vessels.…”

“…Alcohol could also contribute to the apparition of the disease [1,4]. The clinical manifestations are pachyderma thickened facial skin with facial coarsening, acropachia -digital clubbing of hands and feet, periostosis, excessive sweating, arthritis, symmetrical enlargement of forearms and legs [1][2][3][4][5]. The male to female ratio is 7: 1 and the disease is usually begins in childhood or adolescence and progresses slowly for 5 -20 years before stabilizing [1].…”

“…The differential diagnosis should include acromegaly (increased IGF and GH), pachydermoperiostosis secondary to malignanacies, secondary hypertrophic osteoarthropathy (development in adulthood, associated with severe chronic pulmonary diseases, pulmonary malignancies, cyanotic heart diseases) and inflammatory rheumatic diseases [1][2][3][4][5]. The treatment consists usually of long term use of non-steroidal antiinflammatory drugs, joint fluid aspiration, intraarticular glucocorticoids.…”

“…Intravenous pamidronate or zoledronate could improve musculoskeletal symptoms. Surgical interventions could be indicated for skin problems and also for joint involvement [1][2][3][4][5]. Refractory synovitis is rarely reported in pachydermoperiostosis [7].…”