Successful treatment of pachydermoperiostosis with etoricoxib in a patient with a homozygous splice-site mutation in the SLCO2A1 gene

Pseudoacromegaly-A challenging entity in the endocrine clinic: A systematic review

OBJECTIVE

Pseudoacromegaly encompasses conditions with features of acromegaly/gigantism, but no growth hormone (GH) or insulin-like growth factor-1 (IGF-1) excess. We aimed to review published pseudoacromegaly cases evaluated due to clinical suspicion of acromegaly.

DESIGN/PATIENTS

PubMed/Medline search was conducted to identify reported pseudoacromegaly cases, which were systematically reviewed to ensure they met eligibility criteria: (1) presentation suggestive of acromegaly; (2) acromegaly excluded based on normal GH, IGF-1 and/or GH suppression on oral glucose tolerance test (OGTT-GH); (3) diagnosis of the pseudoacromegaly condition was established. Data were retrieved from each case and analysed collectively.

RESULTS

Of 76 cases, 47 were males, mean ages at presentation and at first acromegaloid symptoms were 28 ± 16 and 17 ± 10 years, respectively. Most common conditions were pachydermoperiostosis (47%) and insulin-mediated pseudoacromegaly (IMP) (24%). Acromegaloid facies (75%) and acral enlargement (80%) were the most common features. Measurement of random GH was reported in 65%, IGF-1 in 79%, OGTT-GH in 51%. GH excess was more frequently excluded based on two tests (53%). Magnetic resonance imaging (MRI) was performed in 30 patients, with pituitary adenoma or hyperplasia being reported in eight and three patients, respectively. Investigations differed between cases managed by endocrine and non-endocrine specialists, the former requesting more often IGF-1, OGTT-GH and pituitary MRI.

CONCLUSIONS

Pseudoacromegaly is a challenging entity that may be encountered by endocrinologists. Pachydermoperiostosis and IMP are the conditions most often mimicking acromegaly. Adequate assessment of GH/IGF-1 is crucial to exclude acromegaly, which may be better performed by endocrinologists. Pituitary incidentalomas are common and require careful judgement to prevent unnecessary pituitary surgery.

Genotype and phenotype characterization of primary hypertrophic osteoarthropathy type 2 and chronic enteropathy associated with SLCO2A1: Report of two cases and literature review

Autosomal recessive type 2 primary hypertrophic osteoarthropathy (PHOAR2) and chronic enteropathy associated with SLCO2A1 (CEAS) are two entities caused by pathogenic variants (PVs) in the SLCO2A1 gene that can coexist or occur independently from one another. We report two cases of PHOAR2 in Mexico with concomitant CEAS and conducted a review of the literature of the reported cases of PHOAR2 and/or CEAS to analyze the relationship between their genotype and phenotype presentation. The patients from our Institution with classical PHOAR2 phenotype and CEAS, harbored SLCO2A1 c.547G > A and c.1768del variants. We reviewed 232 cases, of which 86.6% were of Asian origin, and identified 109 different variants in SLCO2A1. Intron 7, exon 13, and exon 4 were predominantly affected. The two most common PVs were c.940 + 1G > A and c.1807C > T. We found a statistically significant association between SLCO2A1 variants located in intron 7, exons 12, and 13 and the development of CEAS. Missense variants were more frequent in isolated PHOAR2, while a greater proportion of protein-truncating variants (PTVs) were found in CEAS. Further investigation is imperative to elucidate the underlying pathophysiological mechanisms associated with CEAS, thereby facilitating the identification of effective therapeutic interventions.

Pachydermoperiostosis: a case report of initial improvement with etoricoxib

Introduction and importance

Pachydermoperiostosis (PDP) is a syndrome characterised by the triad of pachydermia, digital clubbing and periostosis of long bones and its scarce incidence and similarity in clinical features with acromegaly makes the diagnosis challenging. The elevated PGE2 levels have been hypothesised as one of its mechanisms and therapies have been targeted to inhibit this prostaglandin.

Case presentation

A 25-year-old man with no comorbidities presented to OPD with a 10-year history of bilateral pain and swelling of the hands and feets associated with hyperhidrosis, grade IV clubbing and marked skin thickening on his forehead. X-rays revealed hyperostosis of the metacarpals, proximal and middle phalanges and periosteal bone formation with cortical thickening of the ankle joint. Tests done to rule out differentials such as thyroid acropachy, acromegaly, psoriatic arthritis were normal and a clinical diagnosis of PDP, a rare genetic disease characterised by pachyderma, digital clubbing and periostosis was made.

Clinical discussion

The patient was managed conservatively with etoricoxib for 6 months on a follow-up basis. The symptoms were improving and a repeat X-ray showed partial improvement of soft tissue thickening and periostosis.

Conclusion

PDP is a rare diagnosis with no clear consensus on a management approach. Its management with selective COX-2 inhibitors such as etoricoxib should be considered but its long-term effects should be studied further.

A Complete Form of Pachydermoperiostosis Accompanied by a Pituitary Microadenoma

Pachydermoperiostosis is a rare genetic disease that is associated with HPGD (15-hydroxyprostaglandin dehydrogenase) and SLCO2A1 (solute carrier organic anion transporter family member 2A1) gene mutations. It is characterized by three major phenotypes, namely, pachydermia, periostosis, and digital clubbing. Clinically, misdiagnoses such as acromegaly and thyroid acropachy are commonly confused with pachydermoperiostosis. Integral medical history, physical examination, endocrinological tests, and multiple disciplinary cooperation are extremely significant in the accurate diagnosis of pachydermoperiostosis. The co-existence of pachydermoperiostosis and pituitary adenoma is rarely recorded and discussed. In this case, we present a young male patient with a complete form of pachydermoperiostosis and a nonfunctional pituitary microadenoma, which has rarely been reported.

Approach to the Patient With Pseudoacromegaly

Pseudoacromegaly encompasses a heterogeneous group of conditions in which patients have clinical features of acromegaly or gigantism, but no excess of GH or IGF-1. Acromegaloid physical features or accelerated growth in a patient may prompt referral to endocrinologists. Because pseudoacromegaly conditions are rare and heterogeneous, often with overlapping clinical features, the underlying diagnosis may be challenging to establish. As many of these have a genetic origin, such as pachydermoperiostosis, Sotos syndrome, Weaver syndrome, or Cantú syndrome, collaboration is key with clinical geneticists in the diagnosis of these patients. Although rare, awareness of these uncommon conditions and their characteristic features will help their timely recognition.

Primary hypertrophic osteoarthropathy related gastrointestinal complication has distinctive clinical and pathological characteristics: two cases report and review of the literature

BACKGROUND

Primary hypertrophic osteoarthropathy (PHO) is a rare disease related to HPGD and SLCO2A1 gene mutation. Gastrointestinal involvement of PHO is even rarer with unknown pathogenesis. Clinical features of GI complication in PHO mimics other auto-immune based bowel entities, such as inflammatory bowel diseases and cryptogenic multifocal ulcerous stenosing enteritis (CMUSE). We aimed to analyze the clinical, genetic, radiological and pathological features of Chinese patients with PHO and determine the difference between PHO patients presenting with and without GI involvement.

METHODS

We reported two PHO cases with gastrointestinal involvement and reviewed all the studies of PHO in Chinese population published from January 1, 2000, to April 30, 2018. Clinical and genetic presentations of PHO in Chinese patients were analyzed. We compared the characteristics of those patients with gastrointestinal involvement against those without.

RESULTS

The two patients were both males with complete-form PHO for more than 10 years. GI related symptoms included diarrhea, chronic gastrointestinal hemorrhage, incomplete intestinal obstruction, anemia, and edema, which were unresponsive to etoricoxib treatment. Radiological examinations revealed segmental intestinal stenosis and thickened intestinal wall. Endoscopic findings included multiple ulcers and mucosal inflammation. Both patients had mutations of SLCO2A1 according to sequence analysis. The surgical pathology revealed chronic inflammation involving the intestinal mucosa and submucosa, similar to histological changes in CMUSE. According to the systemic review of 158 Chinese patients with PHO, 17.2% had gastrointestinal involvement, including peptic ulcer, gastric polyps, hypertrophic gastritis, and segmental intestinal stenosis. Patients with gastrointestinal involvement were more likely to have anemia (40.0% vs. 4.5%, P < 0.001), hypoalbuminemia (16.7% vs. 0.9%, P = 0.003), and myelofibrosis (19.0% vs. 0.9%, P = 0.002) than those without. Most patients with gastrointestinal complication had SLCO2A1 mutation (86.7%, 13 /15).

CONCLUSIONS

Digestive tract involvement is uncommon in patients with PHO and often presents with anemia, and hypoalbuminemia resulted from intestinal inflammation. The intestinal pathologic characteristics are distinct from Crohn's disease but similar to CMUSE. Mutations in SLCO2A1 might be the pathogenic cause of GI involvement of PHO. NSAIDs may not be effective for PHO patients with gastrointestinal complications.

Pachydermoperiostosis: The value of molecular diagnosis

BACKGROUND

Pachydermoperiostosis is a rare autosomal recessive genetic disorder characterized by the association of periostosis and pachydermia. To date, two genes involved in prostaglandin metabolism, HPGD and SLCO2A1, have been identified.

PATIENTS AND METHODS

A 7-year-old girl presented digital clubbing of the hands and feet, curved nails, hyperhidrosis, and pachydermia, as well as eczema of the trunk and limbs. The diagnosis of pachydermoperiostosis was confirmed by the detection of a homozygous mutation in the HPGD gene. The second case concerned a 41-year-old male with acral and cephalic pachydermia (cutis verticis gyrata), and palmoplantar keratoderma. Bone X-rays showed changes in the distal ends of several bones. The diagnosis of pachydermoperiostosis was confirmed by the detection of a homozygous mutation in the SLCO2A1 gene.

DISCUSSION

The genotype/phenotype correlation suggests that patients with SLCO2A1 mutations will develop the symptoms later in life, but that these will be more severe, with a greater likelihood of cutis verticis gyrata and joint involvement compared with patients presenting HPGD mutations. In addition, hereditary enteropathy has recently been described in patients with SLCO2A1 mutations, which could account for the gastrointestinal picture seen in the second patient. Finally, on account of cases involving myelofibrosis associated with mutations in the SLCO2A gene, these patients should have a hematologic follow-up.

CONCLUSION

Given the genotype/phenotype correlations illustrated by these cases, it would appear useful to propose molecular diagnosis for patients presenting pachydermoperiostosis.

Interleukin-6, tumor necrosis factor-alpha and receptor activator of nuclear factor kappa ligand are elevated in hypertrophic gastric mucosa of pachydermoperiostosis

Pachydermoperiostosis (PDP) is a rare inherited multisystem disease characterized with digital clubbing, pachydermia and periostosis. Variants in either HPGD or SLCO2A1 that interrupt the prostaglandin E2 (PGE₂) pathway have been shown to be involved in PDP. Here, in addition to six confirmed variants in HPGD or SLCO2A1, we identified four novel SLCO2A1 variants in eight PDP patients from seven Chinese Han families. In addition, gastric mucosa hyperplasia was observed in all affected individuals and interleukin-6 (IL-6), tumor necrosis factor-alpha (TNFα) and receptor activator of nuclear factor kappa ligand (RANKL) expression were elevated in hypertrophic gastric mucosa. Two of eight patients who had severe arthralgia were treated with celecoxib. After three months, their arthralgia was partly relieved and IL-6, TNFα and RANKL expression were decreased in accordance with their relieved hypertrophic gastric mucosa. Our study broadens the variation spectrum of SLCO2A1 and suggests that the gastric mucosa hyperplasia might be a common characteristic of PDP. Moreover, celecoxib would be a considerable choice for PDP patients. We also revealed that IL-6, TNFα and RANKL may play important roles in the molecular mechanisms of gastric mucosa hyperplasia in PDP for the first time.

Pachydermoperiostosis Masquerading as Acromegaly

Context:

Acromegaly usually is suspected on clinical grounds. Biochemical confirmation is required to optimize therapy, but there are other differential diagnoses.

Case Description:

We describe a 24-year-old Uzbek man who presented with many clinical symptoms and signs of apparent acromegaly. On examination, the patient showed a rugose folding of his scalp, with the formation of tender, painful, rough skin folds in the parietal-occipital region, resembling cerebral gyri (i.e., cutis verticis gyrate). There was also a thickening and enlargement of the eyelids due to cartilaginous hypertrophy, dystrophic changes of the conjunctiva, and atrophy of the Meibomian glands, with the formation of multiple cysts and granulomas. He perspired excessively. There was thickening of the facial skin, with increased oiliness, increased rugosity, and seborrheic dermatitis. The skin over the hands was thick and apparently fixed to the underlying tissues. However, the patient had a low-normal insulin-like growth factor-1 level. More detailed analysis revealed a family history of relatives with similar problems, and certain features were not in keeping with this diagnosis. The disorder pachydermoperiostosis, or pulmonary hypertrophic osteoarthropathy, was suspected, and next-generation screening confirmed that the patient was homozygous for a pathogenic mutation in the SLCO2A1 gene, c.764G>A (p.Gly255Glu).

Conclusion:

The condition of pachydermoperiostosis may masquerade as acromegaly but is a genetic disorder, usually autosomal recessive, leading to elevated prostaglandin E2 levels. This is an important, albeit rare, differential diagnosis of acromegaly.