An intricate case of sporadic pseudohypoparathyroidism type 1B with a review of literature

SUMMARY Pseudohypoparathyroidism comprehends an assorted group of genetically rare disorders that share end-organ resistance to parathyroid hormone. Genetic and epigenetic modifications on guanine nucleotide-binding protein alpha-stimulating gene locus are the most common underlying mechanisms associated with pseudohypoparathyroidism. Biochemical and molecular analysis stratify pseudohypoparathyroidism into types 1A, 1B, 1C, and 2. We describe an unusual case of sporadic pseudohypoparathyroidism type 1B. A 34-year-old Caucasian woman was admitted to the emergency department, with persistent asthenia, limb paresthesias, and tactile hyposensitivity. Her physical examination, previous personal and family histories were unsuspicious, except for mild, intermittent and self-limited complaints of paresthesia during her two pregnancies, but no detailed workup was done. No typical features of Albright hereditary osteodystrophy were observed. The initial laboratory investigation showed elevated parathyroid hormone level (311.2 pg/mL), hypocalcemia (albumin-corrected serum calcium 4.3 mg/dL), hypocalciuria, hyperphosphatemia, hypophosphaturia, and vitamin D deficiency. Combined calcium, vitamin D, and magnesium supplementation was commenced, with symptomatic and analytical improvement. Albeit resolution of vitamin D deficiency, the patient relapsed with mild and intermittent lower limb paresthesias. Pseudohypoparathyroidism was confirmed by molecular identification of the 3-kb STX16 deletion. The treatment was readjusted, and one year later, symptomatic remission was attained. Clinical and biochemical features, and their respective course, along with lack of distinctive features of Albright hereditary osteodystrophy pointed to pseudohypoparathyroidism type 1B. A careful follow-up is needed to avoid complications and recurrence. Once correction of hypocalcemia and hyperphosphatemia is achieved, with no reported complications and recurrence, a good prognosis is anticipated, comparable to the general population.

An intricate case of sporadic pseudohypoparathyroidism type 1B with a review of literature.

Pseudohypoparathyroidism comprehends an assorted group of genetically rare disorders that share end-organ resistance to parathyroid hormone. Genetic and epigenetic modifications on guanine nucleotide-binding protein alpha-stimulating gene locus are the most common underlying mechanisms associated with pseudohypoparathyroidism. Biochemical and molecular analysis stratify pseudohypoparathyroidism into types 1A, 1B, 1C, and 2. We describe an unusual case of sporadic pseudohypoparathyroidism type 1B. A 34-year-old Caucasian woman was admitted to the emergency department, with persistent asthenia, limb paresthesias, and tactile hyposensitivity. Her physical examination, previous personal and family histories were unsuspicious, except for mild, intermittent and self-limited complaints of paresthesia during her two pregnancies, but no detailed workup was done. No typical features of Albright hereditary osteodystrophy were observed. The initial laboratory investigation showed elevated parathyroid hormone level (311.2 pg/mL), hypocalcemia (albumin-corrected serum calcium 4.3 mg/dL), hypocalciuria, hyperphosphatemia, hypophosphaturia, and vitamin D deficiency. Combined calcium, vitamin D, and magnesium supplementation was commenced, with symptomatic and analytical improvement. Albeit resolution of vitamin D deficiency, the patient relapsed with mild and intermittent lower limb paresthesias. Pseudohypoparathyroidism was confirmed by molecular identification of the 3-kb STX16 deletion. The treatment was readjusted, and one year later, symptomatic remission was attained. Clinical and biochemical features, and their respective course, along with lack of distinctive features of Albright hereditary osteodystrophy pointed to pseudohypoparathyroidism type 1B. A careful follow-up is needed to avoid complications and recurrence. Once correction of hypocalcemia and hyperphosphatemia is achieved, with no reported complications and recurrence, a good prognosis is anticipated, comparable to the general population.

Intragenic Deletions of GNAS in Pseudohypoparathyroidism Type 1A Identify a New Region Affecting Methylation of Exon A/B.

CONTEXT: Pseudohypoparathyroidism type 1A (PHP1A) and pseudopseudohypoparathyroidism (PPHP) are caused by inactivating mutations in the exons of GNAS that encode the alpha-subunit of the stimulatory G protein (Gsα). In some cases abnormal methylation of exon A/B of GNAS, a hallmark of PHP1B, has been reported. OBJECTIVE: To identify the underlying genetic basis for PHP1A/PPHP in patients in whom molecular defects were not detected by GNAS sequencing and microarray-based analysis of copy number variations. METHODS: Whole genome sequencing (WGS) and pyrosequencing of differentially methylated regions (DMRs) of GNAS using genomic deoxyribonucleic acid from affected patients. RESULTS: We identified 2 novel heterozygous GNAS deletions: a 6.4 kb deletion that includes exon 2 of GNAS in the first proband that was associated with normal methylation (57%) of exon A/B DMR, and a 1438 bp deletion in a second PHP1A patient that encompasses the promoter region and 5' untranslated region of Gsα transcripts, which was inherited from his mother with PPHP. This deletion was associated with reduced methylation (32%) of exon A/B DMR. CONCLUSIONS: WGS can detect exonic and intronic mutations, including deletions that are too small to be identified by microarray analysis, and therefore is more sensitive than other techniques for molecular analysis of PHP1A/PPHP. One of the deletions we identified led to reduced methylation of exon A/B DMR, further refining a region needed for normal imprinting of this DMR. We propose that deletion of this region can explain why some PHP1A patients have reduced of methylation of the exon A/B DMR.

Seudohipoparatiroidismo 1b / Pseudohypoparathyroidism 1b

RESUMEN El seudohipoparatiroidismo 1b se caracteriza por resistencia aislada a la parathormona, en ausencia de las manifestaciones típicas de la osteodisfrofia hereditaria de Albright; debido a alteraciones epigenéticas del locus GNAS. Puede presentarse de forma esporádica, o heredado de manera autosómico dominante por vía materna. Se presenta paciente masculino de 31 años, con antecedentes de tumores óseos y calcificaciones cerebrales diagnosticados a los 14 años; que se consulta por presentar mareo intenso, rigidez del cuello y la boca, dificultad para hablar y tragar, desorientación y trastornos de percepción; con fenotipo y somatometría normales, y signos de tetania latente (Chvostek y Trouseau positivos). Los estudios realizados mostraron: hipocalcemia, hiperfosfatemia, aumento de niveles de parathormona y múltiples calcificaciones en cerebro y cerebelo. Con tales hallazgos se emite el diagnóstico de seudohipoparatiroidismo 1b, el cual se confirma mediante pruebas moleculares con alteración en el patrón de metilación en el locus GNAS. No presentó alteraciones en el estudio de secuenciación de los 13 exones codificantes del GNAS. Se concluyó como un caso esporádico ante la ausencia de historia familiar de hipocalcemia, combinado con amplia pérdida de metilación del gen GNAS y la no evidencia de deleciones. Se presenta el primer reporte de esta enfermedad en Cuba con estudio molecular(AU)

ABSTRACT Pseudohypoparathyroidism 1b is characterized by isolated resistance to parathormone, in the absence of the typical manifestations of hereditary Albright osteodysphrophy; due to epigenetic alterations of the GNAS locus. It can occur sporadically, or inherited in an autosomal dominant way through the mother. We report the case of a 31-year-old male patient, with history of bone tumors and cerebral calcifications diagnosed at age 14. She came to consultation due to severe dizziness, stiff neck and mouth, difficulty speaking and swallowing, disorientation and perception disorders; he showed normal phenotype and somatometry, and signs of latent tetany (positive Chvostek and Trouseau). Studies have shown hypocalcaemia, hyperphosphatemia, increased levels of parathormone and multiple calcifications in the brain and cerebellum. These findings, pseudohypoparathyroidism 1b is diagnosed confirmed by molecular tests showing alteration in the methylation pattern in the GNAS locus. There were no alterations in the sequencing study of the 13 exons coding for GNAS. It was concluded as a sporadic case in the absence of a family history of hypocalcemia, combined with extensive loss of GNAS gene methylation and no evidence of deletions. This is the first report this disease with molecular study in Cuba(AU)

[Pseudohypoparathyroidism: report of two cases of late presentation]. / Pseudohipoparatiroidismo de presentación tardía: reporte de dos casos.

Pseudohypoparathyroidism (PHP) is a group of rare genetic disorders that share organ targeted resistance to the action of parathyroid hormone (PTH) as a common feature. Biochemically, they may present with hypocalcemia, hyperphosphatemia and elevated PTH. Some forms present with a specific phenotype: short stature, round facies, short neck, obesity, brachydactyly and subcutaneous calcifications, called Albrigth's Hereditary Osteodystrophy (AHO). This spectrum of disorders are caused by several alterations in the gene coding for the alpha subunit of the G protein (GNAS): an ubiquitous signaling protein that mediates the action of numerous hormones such as PTH, TSH, gonadotropins, and ACTH, among others. According to their inheritance with maternal or paternal imprinting, they may manifest in a diversity of clinical forms. Although most commonly diagnosed during childhood, PHP may manifest clinically during adolescence or early adulthood. We report two late presenting cases of pseudohypoparathyroidism. A 21-year-old female with biochemical abnormalities characteristic of pseudohypoparathyroidism who was misdiagnosed as epilepsy and a 13-year-old boy with the classic AHO phenotype but without alterations in phospho-calcium metabolism, compatible with pseudopseudohypoparathyrodism.

Prevalence of Nephrocalcinosis in Pseudohypoparathyroidism: Is Screening Necessary?

The prevalence of nephrocalcinosis in persons with pseudohypoparathyroidism has not been systematically examined. We conducted a retrospective study of renal imaging and biochemical results in 19 patients with pseudohypoparathyroidism with 49 imaging assessments. No cases of nephrocalcinosis were identified. Routine screening for nephrocalcinosis in pseudohypoparathyroidism may not be necessary.

Pseudohipoparatiroidismo de presentación tardía: reporte de dos casos / Pseudohypoparathyroidism: report of two cases of late presentation

Pseudohypoparathyroidism (PHP) is a group of rare genetic disorders that share organ targeted resistance to the action of parathyroid hormone (PTH) as a common feature. Biochemically, they may present with hypocalcemia, hyperphosphatemia and elevated PTH. Some forms present with a specific phenotype: short stature, round facies, short neck, obesity, brachydactyly and subcutaneous calcifications, called Albrigth's Hereditary Osteodystrophy (AHO). This spectrum of disorders are caused by several alterations in the gene coding for the alpha subunit of the G protein (GNAS): an ubiquitous signaling protein that mediates the action of numerous hormones such as PTH, TSH, gonadotropins, and ACTH, among others. According to their inheritance with maternal or paternal imprinting, they may manifest in a diversity of clinical forms. Although most commonly diagnosed during childhood, PHP may manifest clinically during adolescence or early adulthood. We report two late presenting cases of pseudohypoparathyroidism. A 21-year-old female with biochemical abnormalities characteristic of pseudohypoparathyroidism who was misdiagnosed as epilepsy and a 13-year-old boy with the classic AHO phenotype but without alterations in phospho-calcium metabolism, compatible with pseudopseudohypoparathyrodism.

Hypoparathyroidism and pseudohypoparathyroidism: etiology, laboratory features and complications.

OBJECTIVES: To identify a clinical profile and laboratory findings of a cohort of hypoparathyroidism patients and determine the prevalence and predictors for renal abnormalities. MATERIALS AND METHODS: Data from medical records of five different visits were obtained, focusing on therapeutic doses of calcium and vitamin D, on laboratory tests and renal ultrasonography (USG). RESULTS: Fifty-five patients were identified, 42 females and 13 males; mean age of 44.5 and average time of the disease of 11.2 years. The most frequent etiology was post-surgical. Levels of serum calcium and creatinine increased between the first and last visits (p < 0.001 and p < 0.05, respectively); and serum levels of phosphate decreased during the same period (p < 0.001). Out of the 55 patients, 40 had USG, and 10 (25%) presented with kidney calcifications. There was no significant difference in the amount of calcium and vitamin D doses among patients with kidney calcifications and others. No correlation between serum and urinary levels of calcium and the presence of calcification was found. Urinary calcium excretion in 24h was significantly higher in patients with kidney calcification (3.3 mg/kg/d) than in those without calcification (1.8 mg/kg/d) (p < 0.05). CONCLUSIONS: The reduction of hypocalcemia and hyperphosphatemia suggest an effectiveness of the treatment, and the increase in serum creatinine demonstrates an impairment of renal function during follow-up. Kidney calcifications were prevalent in this cohort, and higher urinary calcium excretion, even if still within the normal range, was associated with development of calcification. These findings suggest that lower rates of urinary calcium excretion should be aimed for in the management of hypoparathyroidism.

Hypoparathyroidism and pseudohypoparathyroidism: etiology, laboratory features and complications

ABSTRACT Objectives To identify a clinical profile and laboratory findings of a cohort of hypoparathyroidism patients and determine the prevalence and predictors for renal abnormalities. Materials and methods Data from medical records of five different visits were obtained, focusing on therapeutic doses of calcium and vitamin D, on laboratory tests and renal ultrasonography (USG). Results Fifty-five patients were identified, 42 females and 13 males; mean age of 44.5 and average time of the disease of 11.2 years. The most frequent etiology was post-surgical. Levels of serum calcium and creatinine increased between the first and last visits (p < 0.001 and p < 0.05, respectively); and serum levels of phosphate decreased during the same period (p < 0.001). Out of the 55 patients, 40 had USG, and 10 (25%) presented with kidney calcifications. There was no significant difference in the amount of calcium and vitamin D doses among patients with kidney calcifications and others. No correlation between serum and urinary levels of calcium and the presence of calcification was found. Urinary calcium excretion in 24h was significantly higher in patients with kidney calcification (3.3 mg/kg/d) than in those without calcification (1.8 mg/kg/d) (p < 0.05). Conclusions The reduction of hypocalcemia and hyperphosphatemia suggest an effectiveness of the treatment, and the increase in serum creatinine demonstrates an impairment of renal function during follow-up. Kidney calcifications were prevalent in this cohort, and higher urinary calcium excretion, even if still within the normal range, was associated with development of calcification. These findings suggest that lower rates of urinary calcium excretion should be aimed for in the management of hypoparathyroidism.

Doença de Fahr: relato de caso / Fahr's syndrome: a case report

A doença de Fahr é uma doença rara, que apresenta calcificação idiopática bilateral nos núcleos da base, e outros locais do SNC como cerebelo, de origem esporádica ou familiar. O paciente do atual estudo foi admitido no Hospital Municipal Dr. Carmino Caricchio com relato de disartria, diplegia, astenia e tremores em repouso, de caráter esporádico há 3 meses, tendo o mesmo previamente procurado auxilio médico em outros serviços e sido orientado sobre diagnóstico inicial de Síndrome de Parkinson.

Avaliação fenotípica e de defeitos moleculares no GNAS em pacientes com pseudo-hipoparatireoidismo (PHP) e pseudopseudo-hipoparatireoidismo (PPHP) / Evaluation of the phenotype and molecular defect in GNAS in patients with pseudohypoparathyroidism (PHP) and pseudopseudohypoparathyroidism

INTRODUÇÃO: A primeira doença humana atribuída à resistência hormonal foi o pseudo-hipoparatireoidismo (PHP), uma doença rara caracterizada por hipocalcemia, hiperfosfatemia e níveis elevados de hormônio paratireoidiano (PTH) na presença de função renal normal, quadro condizente com resistência ao PTH. A classificação original do PHP leva em consideração a osteodistrofia hereditária de Albright (AHO): presente no PHP1a e ausente no PHP1b. Na medida em que as bases moleculares do PHP têm sido compreendidas, uma classificação baseada no genótipo tem surgido. Segundo ela, pacientes com PHP1a apresentam mutações na região codificadora da Gsalfa do GNAS e o padrão de herança é autossômico dominante relacionado à transmissão materna. Por outro lado, o PHP1b é caracterizado por alterações nas regiões diferencialmente metiladas (DMRs) do GNAS por mecanismos não completamente esclarecidos, limitando a previsão do seu padrão de herança. Pacientes que apresentam a AHO na ausência de resistência hormonal têm o diagnóstico de pseudopseudo-hipoparatireoidismo (PPHP) e seu padrão de herança é autossômico dominante relacionado à transmissão paterna de mutações na região codificadora da Gsalfa do GNAS. OBJETIVOS: Classificar 25 pacientes com PHP com base em defeitos no GNAS e caracterizar seu fenótipo. Pesquisar mutações no GNAS nos quatro pacientes com PPHP e também caracterizar seu fenótipo. MÉTODOS: A avaliação fenotípica incluiu análise das resistências hormonais, pesquisa de repercussões crônicas da hipocalcemia/hiperfosfatemia (calcificações em sistema nervoso central: SNC e catarata) e identificação da AHO. A análise do GNAS foi feita por sequenciamento automático e MLPA (região codificadora da Gsalfa) e por MS-MLPA (região regulatória: DMRs). RESULTADOS: Resistência ao PTH foi identificada nos 25 pacientes com PHP e resistência ao TSH em 17/25. Calcificações em SNC e catarata estiveram presentes em 18 e 10 pacientes com PHP, respectivamente. A...

BACKGROUND: The first human disease attributed to hormone resistance was pseudohypoparathyroidism (PHP), a rare disease characterized by hypocalcemia, hyperphosphatemia and elevated parathyroid hormone (PTH) levels in the presence of normal renal function, consistent picture of PTH resistance. The original classification of PHP takes into account the Albright hereditary osteodystrophy (AHO): present in PHP1a and absent in PHP1b. As the molecular bases of PHP have been understood, a classification based on genotype has emerged. According to it, PHP1a patients present mutations in the Gsalpha coding region of the GNAS and the pattern of inheritance is autosomal dominant related to maternal transmission. On the other hand, PHP1b is characterized by alterations in differentially methylated regions (DMRs) of the GNAS by mechanisms not completely clear, limiting the prediction of the pattern of inheritance. Patients who present AHO in the absence of hormone resistance have the diagnosis of pseudopseudohypoparathyroidism (PPHP) and their pattern of inheritance is autosomal dominant related to paternal transmission of mutations in the Gsalfa coding region of the GNAS. OBJECTIVE: To classify 25 patients with PHP based on GNAS molecular defects and to characterize their phenotype. To search for GNAS mutations in four patients with PPHP and also to characterize their phenotype. METHODS: The phenotypic evaluation included analysis of hormone resistances, research of chronic repercussions of hypocalcemia/hyperphosphatemia (calcifications in central nervous system: CNS and cataract) and identification of AHO. The analysis of the GNAS was done by automated sequencing and MLPA (Gsalphaa coding region) and by MS-MLPA (regulatory region: DMRs). RESULTS: PTH resistance was identified in 25 patients with PHP and TSH resistance in 17/25. Calcifications in CNS and cataract were present in 18 and 10 patients with PHP, respectively. AHO was characterized by: rounded face (n=18),...

Pseudohypoparathyroidism type Ia: a novel GNAS mutation in a Brazilian boy presenting with an early primary hypothyroidism.

Pseudohypoparathyroidism type Ia (PHP Ia) is a rare disease characterized by an elevated parathyroid hormone due to the resistance to its action in target tissues. We report a new GNAS mutation causing PHP Ia and an atypical early-onset primary hypothyroidism. A 3-year-old boy was diagnosed with obesity, delayed pyschomotor development, and round face. The laboratory evaluation at the age of 1 year showed primary hypothyroidism, hypocalcemia, hyperphosphatemia, elevated alkaline phosphatase, and parathyroid hormone. These data led to the diagnosis of PHP Ia. Molecular analysis revealed a novel missense mutation in GNAS exon 1 (TCG→CGC, Cys3→Arg) in both the child and his mother. Although previously reported cases described delayed subclinical hypothyroidism as the more common thyroid abnormality, we report a not previously described GNAS mutation associated with an atypical early-onset primary hypothyroidism. These observations broaden the clinical spectrum of PHP Ia and its associated mutations.

Coexistence of glucocorticoid resistance and pseudohypoparathyroidism / Coexistencia de la resistencia a glucocorticoides y el pseudohipoparatiroidismo

We report for the first time the case of a young man who developed both glucocorticoid resistance and resistance to parathyroid hormone. Treatment with high doses of dexamethasone together with administration of calcium and calcitriol resulted in a significant improvement in the patient's condition. In this paper, we discuss in detail diagnostic and treatment strategies used on the patient and the impact on the course and outcome of both disorders. We associate the development of both these disorders with a possible inherited defect in the signal pathways common to glucocorticoid and parathyroid hormone receptors.

Por primera vez se reporta el caso de un joven que desarrolló resistencia a glucocorticoides y resistencia a la hormona paratiroidea. El tratamiento con altas dosis de dexametasona, junto con la administración de calcio y calcitriol, trajo como resultado una mejoría significativa de la condición del paciente. En este papel, se analiza en detalle el diagnóstico así como las estrategias de tratamiento del paciente, y su impacto en el curso y resultado de ambos trastornos. Se concluye que el desarrollo de ambos trastornos se halla asociado a un posible defecto hereditario en las vías de transducción de señales comunes a los receptores de las hormonas glucocorticoides y las hormonas paratiroideas.

Hipocalcemia asociada a hiperfosfemia y PTH elevada: caso clínico / Hypocalcemia, vitamin D deficiency and elevated PTH levels in a patient with celiac disease: report of one case

We report a 56 years old woman that presented a severe hypocalcemia, with a serum calcium of 4.7 mg/dl, after the intake of bisphosphonates. Laboratory examination showed elevated PTH levels (167 pg/ml), hyperphosphatemia, hypomagnesemia and normal phosphate tubular reabsorption. Therefore, the diagnosis of pseudohypoparathyroidism was considered (PHP). However, further studies showed low levels of 25 OH Vitamin D (13.6 ng /ml), osteoporosis, positive anti endomysium antibodies and an endoscopic biopsy, that confirmed the presence of a celiac disease.

Coexistence of glucocorticoid resistance and pseudohypoparathyroidism.

We report for the first time the case of a young man who developed both glucocorticoid resistance and resistance to parathyroid hormone. Treatment with high doses of dexamethasone together with administration of calcium and calcitriol resulted in a significant improvement in the patients condition. In this paper, we discuss in detail diagnostic and treatment strategies used on the patient and the impact on the course and outcome of both disorders. We associate the development of both these disorders with a possible inherited defect in the signal pathways common to glucocorticoid and parathyroid hormone receptors.

A novel GNAS mutation in an infant boy with pseudohypoparathyroidism type Ia and normal serum calcium and phosphate levels / Mutação nova no GNAS em um menino com pseudo-hipoparatireoidismo tipo Ia e dosagens séricas normais de cálcio e fósforo

The objective of this study was to describe a new mutation in GNAS in a family with pseudohypoparathyroidism type Ia (PHP Ia), a rare osteometabolic disease. An 8-month-old boy was seen by an Endocrinologist due to obesity and low growth velocity. Noteworthy, his mother exhibited typical Albright hereditary osteodystrophy (AHO) phenotype. The clinical diagnosis of PHP Ia was suspected. The GNAS coding region from mother and son was amplified and directly sequenced. A novel heterozygous missense mutation (c.673T>C) was identified in exon 5 in both patients. In this family, the mother's clinical picture was the clue for the son's diagnosis. Molecular analysis of GNAS confirmed the diagnosis of PHP Ia in both patients and the child's early diagnosis was possible. Moreover, this novel missense substitution expands the spectrum of GNAS mutations associated with this disorder and allows for genetic counseling of this family.

O objetivo deste estudo foi descrever uma nova mutação no GNAS em uma família com pseudo-hipoparatireoidismo tipo Ia (PHP Ia), doença osteometabólica rara. Um garoto de oito meses foi visto por um endocrinologista por obesidade e baixa velocidade de crescimento. Chamava a atenção o fato de sua mãe apresentar fenótipo típico da osteodistrofia hereditária de Albright (OHA). O diagnóstico clínico de PHP Ia foi suspeitado. A região codificadora do GNAS da mãe e do filho foi amplificada e submetida ao sequenciamento direto. Uma nova mutação missense em heterozigose (c.673T>C) foi identificada no éxon 5 em ambos. O quadro clínico materno foi a pista para o diagnóstico do filho. A análise molecular do GNAS confirmou o diagnóstico de PHP Ia nos dois pacientes possibilitando o diagnóstico precoce da criança. Além disso, essa nova substituição missense expande o espectro de mutações no GNAS associadas a essa doen­ça e permite o aconselhamento genético nesta família.