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Open access

Maria P Yavropoulou, Efstathios Chronopoulos, George Trovas, Emmanouil Avramidis, Francesca Marta Elli, Giovanna Mantovani, Pantelis Zebekakis and John G Yovos

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.

Open access

C Kamath, J Witczak, M A Adlan and L D Premawardhana

Summary

Thymic enlargement (TE) in Graves’ disease (GD) is often diagnosed incidentally when chest imaging is done for unrelated reasons. This is becoming more common as the frequency of chest imaging increases. There are currently no clear guidelines for managing TE in GD. Subject 1 is a 36-year-old female who presented with weight loss, increased thirst and passage of urine and postural symptoms. Investigations confirmed GD, non-PTH-dependent hypercalcaemia and Addison’s disease (AD). CT scans to exclude underlying malignancy showed TE but normal viscera. A diagnosis of hypercalcaemia due to GD and AD was made. Subject 2, a 52-year-old female, was investigated for recurrent chest infections, haemoptysis and weight loss. CT thorax to exclude chest malignancy, showed TE. Planned thoracotomy was postponed when investigations confirmed GD. Subject 3 is a 47-year-old female who presented with breathlessness, chest pain and shakiness. Investigations confirmed T3 toxicosis due to GD. A CT pulmonary angiogram to exclude pulmonary embolism showed TE. The CT appearances in all three subjects were consistent with benign TE. These subjects were given appropriate endocrine treatment only (without biopsy or thymectomy) as CT appearances showed the following appearances of benign TE – arrowhead shape, straight regular margins, absence of calcification and cyst formation and radiodensity equal to surrounding muscle. Furthermore, interval scans confirmed thymic regression of over 60% in 6 months after endocrine control. In subjects with CT appearances consistent with benign TE, a conservative policy with interval CT scans at 6 months after endocrine control will prevent inappropriate surgical intervention.

Learning points:

  • Chest imaging is common in modern clinical practice and incidental anterior mediastinal abnormalities are therefore diagnosed frequently.

  • Thymic enlargement (TE) associated with Graves’ disease (GD) is occasionally seen in view of the above.

  • There is no validated strategy to manage TE in GD at present.

  • However, CT (or MRI) scan features of the thymus may help characterise benign TE, and such subjects do not require thymic biopsy or surgery at presentation.

  • In them, an expectant ‘wait and see’ policy is recommended with GD treatment only, as the thymus will show significant regression 6 months after endocrine control.

Open access

Alejandro García-Castaño, Leire Madariaga, Sharona Azriel, Gustavo Pérez de Nanclares, Idoia Martínez de LaPiscina, Rosa Martínez, Inés Urrutia, Aníbal Aguayo, Sonia Gaztambide and Luis Castaño

Summary

Familial hypocalciuric hypercalcemia type I is an autosomal dominant disorder caused by heterozygous loss-of-function mutations in the CASR gene and is characterized by moderately elevated serum calcium concentrations, low urinary calcium excretion and inappropriately normal or mildly elevated parathyroid hormone (PTH) concentrations. We performed a clinical and genetic characterization of one patient suspected of familial hypocalciuric hypercalcemia type I. Patient presented persistent hypercalcemia with normal PTH and 25-hydroxyvitamin D levels. The CASR was screened for mutations by PCR followed by direct Sanger sequencing and, in order to detect large deletions or duplications, multiplex ligation-dependent probe amplification (MLPA) was used. One large deletion of 973 nucleotides in heterozygous state (c.1733-255_2450del) was detected. This is the first large deletion detected by the MLPA technique in the CASR gene.

Learning points:

  • Molecular studies are important to confirm the differential diagnosis of FHH from primary hyperparathyroidism.

  • Large deletions or duplications in the CASR gene can be detected by the MLPA technique.

  • Understanding the functional impact of the mutations is critical for leading pharmacological research and could facilitate the therapy of patients.

Open access

Haruhiro Sato and Yuichiro Tomita

Summary

Resistance to thyroid hormone (RTH), which is primarily caused by mutations in the thyroid hormone (TH) receptor beta (THRB) gene, is dominantly inherited syndrome of variable tissue hyposensitivity to TH. We herein describe a case involving a 22-year-old Japanese man with RTH and atrial fibrillation (AF) complaining of palpitation and general fatigue. Electrocardiography results revealed AF. He exhibited elevated TH levels and an inappropriately normal level of thyroid-stimulating hormone (TSH). Despite being negative for anti-TSH receptor antibody, thyroid-stimulating antibody and anti-thyroperoxidase antibody, the patient was positive for anti-thyroglobulin (Tg) antibody. Genetic analysis of the THRB gene identified a missense mutation, F269L, leading to the diagnosis of RTH. Normal sinus rhythm was achieved after 1 week of oral bisoprolol fumarate (5 mg/day) administration. After 3 years on bisoprolol fumarate, the patient had been doing well with normal sinus rhythm, syndrome of inappropriate secretion of TSH (SITSH) and positive titer of anti-Tg antibody.

Learning points:

  • Atrial fibrillation can occur in patients with RTH.

  • Only a few cases have been reported on the coexistence of RTH and atrial fibrillation.

  • No consensus exists regarding the management of atrial fibrillation in patients with RTH.

  • Administration of bisoprolol fumarate, a beta-blocker, can ameliorate atrial fibrillation in RTH.

Open access

Kewan Hamid, Neha Dayalani, Muhammad Jabbar and Elna Saah

Summary

A 6-year-old female presented with chronic intermittent abdominal pain for 1 year. She underwent extensive investigation, imaging and invasive procedures with multiple emergency room visits. It caused a significant distress to the patient and the family with multiple missing days at school in addition to financial burden and emotional stress the child endured. When clinical picture was combined with laboratory finding of macrocytic anemia, a diagnosis of hypothyroidism was made. Although chronic abdominal pain in pediatric population is usually due to functional causes such as irritable bowel syndrome, abdominal migraine and functional abdominal pain. Hypothyroidism can have unusual presentation including abdominal pain. The literature on abdominal pain as the main presentation of thyroid disorder is limited. Pediatricians should exclude hypothyroidism in a patient who presents with chronic abdominal pain. Contrast to its treatment, clinical presentation of hypothyroidism can be diverse and challenging, leading to a delay in diagnosis and causing significant morbidity.

Learning points:

  • Hypothyroidism can have a wide range of clinical presentations that are often nonspecific, which can cause difficulty in diagnosis.

  • In pediatric patients presenting with chronic abdominal pain as only symptom, hypothyroidism should be considered by the pediatricians and ruled out.

  • In pediatric population, treatment of hypothyroidism varies depending on patients’ weight and age.

  • Delay in diagnosis of hypothyroidism can cause significant morbidity and distress in pediatrics population.

Open access

Daniela Regazzo, Marina Paola Gardiman, Marily Theodoropoulou, Carla Scaroni, Gianluca Occhi and Filippo Ceccato

Summary

Tuberous sclerosis complex (TSC) is an autosomal dominant multisystem hereditary cutaneous condition, characterized by multiple hamartomas. In rare cases, pituitary neuroendocrine tumors (PitNETs) have been described in patients with TSC, but the causal relationship between these two diseases is still under debate. TSC is mostly caused by mutations of two tumor suppressor genes, encoding for hamartin (TSC1) and tuberin (TSC2), controlling cell growth and proliferation. Here, we present the case of a 62-year-old Caucasian woman with TSC and a silent gonadotroph PitNET with suprasellar extension, treated with transsphenoidal endoscopic neurosurgery with complete resection. Therapeutic approaches based on mTOR signaling (i.e. everolimus) have been successfully used in patients with TSC and tested in non-functioning PitNET cellular models with promising results. Here, we observed a reduction of cell viability after an in vitro treatment of PitNET’s derived primary cells with everolimus. TSC analysis retrieved no disease-associated variants with the exception of the heterozygous intronic variant c.4006-71C>T found in TSC2: the computational tools predicted a gain of a new splice site with consequent intron retention, not confirmed by an in vitro analysis of patient’s lymphocyte-derived RNA. Further analyses are therefore needed to provide insights on the possible mechanisms involving the hamartin-tuberin complex in the pathogenesis of pituitary adenomas. However, our data further support previous observations of an antiproliferative effect of everolimus on PitNET.

Learning points:

  • Pituitary neuroendocrine tumors (PitNET) in patients with tuberous sclerosis complex (TSC) are rare: only few cases have been reported in literature.

  • Therapeutic approach related to mTOR signaling, such as everolimus, may be used in some patients with PitNETs as well as those with TSC.

  • We reported a woman with both non-secreting PitNET and TSC; PitNET was surgically removed and classified as a silent gonadotroph tumor.

  • Everolimus treatment in PitNET’s-derived primary cells revealed a significant decrease in cell viability.

  • Considering our case and available evidence, it is still unclear whether a PitNET is a part of TSC or just a coincidental tumor.

Open access

Eleanor P Thong, Sarah Catford, Julie Fletcher, Phillip Wong, Peter J Fuller, Helena Teede and Frances Milat

Summary

The association between type 1 diabetes mellitus (T1DM) and bone health has garnered interest over the years. Fracture risk is known to be increased in individuals with T1DM, although bone health assessment is not often performed in the clinical setting. We describe the case of a 21-year-old male with longstanding T1DM with multilevel vertebral fractures on imaging, after presenting with acute back pain without apparent trauma. Dual-energy X-ray absorptiometry (DXA) revealed significantly reduced bone mineral density at the lumbar spine and femoral neck. Extensive investigations for other secondary or genetic causes of osteoporosis were unremarkable, apart from moderate vitamin D deficiency. High-resolution peripheral quantitative computed tomography and bone biospy revealed significant alterations of trabecular bone microarchitecture. It later transpired that the patient had sustained vertebral fractures secondary to unrecognised nocturnal hypoglycaemic seizures. Intravenous zoledronic acid was administered for secondary fracture prevention. Despite anti-resorptive therapy, the patient sustained a new vertebral fracture after experiencing another hypoglycaemic seizure in his sleep. Bone health in T1DM is complex and not well understood. There are significant challenges in the assessment and management of osteoporosis in T1DM, particularly in young adults, where fracture prediction tools have not been validated. Clinicians should be aware of hypoglycaemia as a significant risk factor for fracture in patients with T1DM.

Learning points:

  • Type 1 diabetes mellitus (T1DM) is a secondary cause of osteoporosis, characterised by reduced bone mass and disturbed bone microarchitecture.

  • Hypoglycaemic seizures generate sufficient compression forces along the thoracic column and can cause fractures in individuals with compromised bone quality.

  • Unrecognised hypoglycaemic seizures should be considered in patients with T1DM presenting with fractures without a history of trauma.

  • Patients with T1DM have increased fracture risk and risk factors should be addressed. Evaluation of bone microarchitecture may provide further insights into mechanisms of fracture in T1DM.

  • Further research is needed to guide the optimal screening and management of bone health in patients with T1DM.

Open access

N Chelaghma, S O Oyibo and J Rajkanna

Summary

Hypogonadotrophic hypogonadism is due to impaired or reduced gonadotrophin secretion from the pituitary gland. In the absence of any anatomical or functional lesions of the pituitary or hypothalamic gland, the hypogonadotrophic hypogonadism is referred to as idiopathic hypogonadotrophic hypogonadism (IHH). We present a case of a young lady born to consanguineous parents who was found to have IHH due to a rare gene mutation.

Learning points:

  • The genetic basis of a majority of cases of IHH remains unknown.

  • IHH can have different clinical endocrine manifestations.

  • Patients can present late to the healthcare service because of unawareness and stigmata associated with the clinical features.

  • Family members of affected individuals can be affected to varying degrees.

Open access

Jia Xuan Siew and Fabian Yap

Summary

Growth anomaly is a prominent feature in Wolf-Hirschhorn syndrome (WHS), a rare congenital disorder caused by variable deletion of chromosome 4p. While growth charts have been developed for WHS patients 0–4 years of age and growth data available for Japanese WHS patients 0–17 years, information on pubertal growth and final height among WHS children remain lacking. Growth hormone (GH) therapy has been reported in two GH-sufficient children with WHS, allowing for pre-puberty catch up growth; however, pubertal growth and final height information was also unavailable. We describe the complete growth journey of a GH-sufficient girl with WHS from birth until final height (FH), in relation to her mid parental height (MPH) and target range (TR). Her growth trajectory and pubertal changes during childhood, when she was treated with growth hormone (GH) from 3 years 8 months old till 6 months post-menarche at age 11 years was fully detailed.

Learning points:

  • Pubertal growth characteristics and FH information in WHS is lacking.

  • While pre-pubertal growth may be improved by GH, GH therapy may not translate to improvement in FH in WHS patients.

  • Longitudinal growth, puberty and FH data of more WHS patients may improve the understanding of growth in its various phases (infancy/childhood/puberty).

Open access

Natasha Shrikrishnapalasuriyar, Mirena Noyvirt, Philip Evans, Bethan Gibson, Elin Foden and Atul Kalhan

A 54-year-old woman was admitted to hospital with a presumed allergic reaction to a single dose of amoxicillin given for a suspected upper respiratory tract infection. She complained of chest tightness although there was no wheeze or stridor. On examination, she was pyrexial, tachycardic, hypertensive and had a diffuse mottled rash on her lower limbs. Her initial investigations showed raised inflammatory markers. She was treated in the intensive care for a presumed anaphylactic reaction with an underlying sepsis. Further investigations including CT head and CSF examination were unremarkable; however, a CT abdomen showed a 10 cm heterogeneous right adrenal mass. Based on review by the endocrine team, a diagnosis of pheochromocytoma crisis was made, which was subsequently confirmed on 24-h urinary metanephrine measurement. An emergency adrenalectomy was considered although she was deemed unfit for surgery. Despite intensive medical management, her conditioned deteriorated and she died secondary to multi-organ failure induced by pheochromocytoma crisis.

Learning points:

  • Pheochromocytoma have relatively higher prevalence in autopsy series (0.05–1%) suggestive of a diagnosis, which is often missed.

  • Pheochromocytoma crisis is an endocrine emergency characterized by hemodynamic instability induced by surge of catecholamines often precipitated by trauma and medications (β blockers, general anesthetic agents, ephedrine and steroids).

  • Pheochromocytoma crisis can mimic acute coronary syndrome, cardiogenic or septic shock.

  • Livedo reticularis can be a rare although significant cutaneous marker of underlying pheochromocytoma crisis.

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