Diagnosis and Treatment > Signs and Symptoms
Search for other papers by Maria P Yavropoulou in
Google Scholar
PubMed
Search for other papers by Efstathios Chronopoulos in
Google Scholar
PubMed
Search for other papers by George Trovas in
Google Scholar
PubMed
Search for other papers by Emmanouil Avramidis in
Google Scholar
PubMed
Search for other papers by Francesca Marta Elli in
Google Scholar
PubMed
Search for other papers by Giovanna Mantovani in
Google Scholar
PubMed
Search for other papers by Pantelis Zebekakis in
Google Scholar
PubMed
Search for other papers by John G Yovos in
Google Scholar
PubMed
Summary
Pseudohypoparathyroidism (PHP) is a heterogeneous group of rare endocrine disorders characterised by normal renal function and renal resistance to the action of the parathyroid hormone. Type 1A (PHP1A), which is the most common variant, also include developmental and skeletal defects named as Albright hereditary osteodystrophy (AHO). We present two cases, a 54- and a 33-year-old male diagnosed with PHP who were referred to us for persistently high levels of serum calcitonin. AHO and multinodular goitre were present in the 54-year-old male, while the second patient was free of skeletal deformities and his thyroid gland was of normal size and without nodular appearance. We performed GNAS molecular analysis (methylation status and copy number analysis by MS-MLPA) in genomic DNA samples for both patients. The analysis revealed a novel missense variant c.131T>G p.(Leu44Pro) affecting GNAS exon 1, in the patient with the clinical diagnosis of PHP1A. This amino acid change appears to be in accordance with the clinical diagnosis of the patient. The genomic DNA analysis of the second patient revealed the presence of the recurrent 3-kb deletion affecting the imprinting control region localised in the STX16 region associated with the loss of methylation (LOM) at the GNAS A/B differentially methylated region and consistent with the diagnosis of an autosomal dominant form of PHP type 1B (PHP1B). In conclusion, hypercalcitoninaemia may be encountered in PHP1A and PHP1B even in the absence of thyroid pathology.
Learning points:
-
We describe a novel missense variant c.131T>G p.(Leu44Pro) affecting GNAS exon 1 as the cause of PHP1A.
-
Hypercalcitoninaemia in PHP1A is considered an associated resistance to calcitonin, as suggested by the generalised impairment of Gsα-mediated hormone signalling.
-
GNAS methylation defects, as in type PHP1B, without thyroid pathology can also present with hypercalcitoninaemia.
Search for other papers by Alireza Arefzadeh in
Google Scholar
PubMed
Search for other papers by Pooyan Khalighinejad in
Google Scholar
PubMed
Search for other papers by Bahar Ataeinia in
Google Scholar
PubMed
Search for other papers by Pegah Parvar in
Google Scholar
PubMed
Summary
Deletion of chromosome 2q37 results in a rare congenital syndrome known as brachydactyly mental retardation (BDMR) syndrome; a syndrome which has phenotypes similar to Albright hereditary osteodystrophy (AHO) syndrome. In this report, we describe a patient with AHO due to microdeletion in long arm of chromosome 2 [del(2)(q37.3)] who had growth hormone (GH) deficiency, which is a unique feature among reported BDMR cases. This case was presented with shortening of the fourth and fifth metacarpals which along with AHO phenotype, brings pseudopseudohypoparathyroidism (PPHP) and pseudohypoparathyroidism type Ia (PHP-Ia) to mind; however, a genetic study revealed del(2)(q37.3). We recommend clinicians to take BDMR in consideration when they are faced with the features of AHO; although this syndrome is a rare disease, it should be ruled out while diagnosing PPHP or PHP-Ia. Moreover, we recommend evaluation of IGF 1 level and GH stimulation test in patients with BDMR whose height is below the 3rd percentile.
Learning points:
-
Clinicians must have brachydactyly mental retardation (BDMR) syndrome in consideration when they are faced with the features of Albright hereditary osteodystrophy.
-
Although BDMR syndrome is a rare disease, it should be ruled out while diagnosing PPHP or PHP-Ia.
-
Evaluation of IGF1 level in patients diagnosed with BDMR whose height is below the 3rd percentile is important.