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Open access

Sarah W Y Poon, Karen K Y Leung and Joanna Y L Tung

Summary

Severe hypertriglyceridemia is an endocrine emergency and is associated with acute pancreatitis and hyperviscosity syndrome. We describe an infant with lipoprotein lipase deficiency with severe hypertriglyceridemia who presented with acute pancreatitis. She was managed acutely with fasting and intravenous insulin infusion, followed by low-fat diet with no pharmacological agent. Subsequent follow-up until the age of 5 years showed satisfactory lipid profile and she has normal growth and development.

Learning points:

  • Hypertriglyceridemia-induced acute pancreatitis has significant morbidity and mortality, and prompt treatment is imperative.

  • When no secondary causes are readily identified, genetic evaluation should be pursued in hypertriglyceridemia in children.

  • Intravenous insulin is a safe and effective acute treatment for hypertriglyceridemia in children, even in infants.

  • Long-term management with dietary modifications alone could be effective for primary hypertriglyceridemia due to lipoprotein lipase deficiency, at least in early childhood phase.

Open access

Valeria de Miguel, Andrea Paissan, Patricio García Marchiñena, Alberto Jurado, Mariana Isola, José Alfie and Patricia Fainstein-Day

Summary

We present the case of a 25-year-old male with a history of neurofibromatosis type 1 and bilateral pheochromocytoma 4 years after kidney transplantation that was successfully treated with simultaneous bilateral posterior retroperitoneoscopic adrenalectomy.

Learning points:

  • Hypertensive patients with NF1 should always be screened for pheochromocytoma.

  • Pheochromocytoma is rarely associated with transplantation, but it must be ruled out in patients with genetic susceptibility.

  • Posterior retroperitoneoscopic adrenalectomy (PRA) allows more direct access to the adrenal glands, especially in patients with previous abdominal surgeries.

Open access

Himangshu S Bose, Alan M Rice, Brendan Marshall, Fadi Gebrail, David Kupshik and Elizabeth W Perry

Summary

Steroid hormones are essential for the survival of all mammals. In adrenal glands and gonads, cytochrome P450 side chain cleavage enzyme (SCC or CYP11A1), catalyzes conversion of cholesterol to pregnenolone. We studied a patient with ambiguous genitalia by the absence of Müllerian ducts and the presence of an incompletely formed vagina, who had extremely high adrenocorticotropic hormone (ACTH) and reduced pregnenolone levels with enlarged adrenal glands. The testes revealed seminiferous tubules, stroma, rete testis with interstitial fibrosis and reduced number of germ cells. Electron microscopy showed that the patient’s testicular mitochondrial size was small with little SCC expression within the mitochondria. The mitochondria were not close to the mitochondria-associated ER membrane (MAM), and cells were filled with the microfilaments. Our result revealed that absence of pregnenolone is associated with organelle stress, leading to altered protein organization that likely created steric hindrance in testicular cells.

Learning points:

  • Testes revealed seminiferous tubules, stroma, rete testis with interstitial fibrosis and reduced number of germ cells;

  • Testicular mitochondrial size was small with little SCC expression within the mitochondria;

  • Absence of pregnenolone is associated with organelle stress.

Open access

H Joshi, M Hikmat, A P Devadass, S O Oyibo and S V Sagi

Summary

IgG4-related disease (IgG4-RD) is an immune-mediated fibro-inflammatory condition which can affect various organs including the pituitary gland. The true annual incidence of this condition remains widely unknown. In addition, it is unclear whether IgG4 antibodies are causative or the end result of a trigger. With no specific biomarkers available, the diagnosis of IgG4-related hypophysitis remains a challenge. Additionally, there is a wide differential diagnosis. We report a case of biopsy-proven IgG4-related hypophysitis in a young man with type 2 diabetes mellitus.

Learning points:

  • IgG4-related hypophysitis is part of a spectrum of IgG4-related diseases.

  • Clinical manifestations result from anterior pituitary hormone deficiencies with or without diabetes insipidus, which can be temporary or permanent.

  • A combination of clinical, radiological, serological and histological evidence with careful interpretation is required to make the diagnosis.

  • Tissue biopsy remains the gold standard investigation.

  • Disease monitoring and long-term management of this condition is a challenge as relapses occur frequently.

Open access

Jill Pancer, Elliot Mitmaker, Oluyomi Ajise, Roger Tabah and Jacques How

Summary

Multifocal papillary thyroid carcinoma (PTC) is common and the number of tumor foci rarely exceeds ten. The mechanism of multifocal disease is debated, with the two main hypotheses consisting of either intrathyroidal metastatic spread from a single tumor or independent multicentric tumorigenesis from distinct progenitor cells. We report the case of a 46-year-old woman who underwent total thyroidectomy and left central neck lymph node dissection after fine-needle aspiration of bilateral thyroid nodules that yielded cytological findings consistent with PTC. Final pathology of the surgical specimen showed an isthmic dominant 1.5 cm classical PTC and over 30 foci of microcarcinoma, which displayed decreasing density with increasing distance from the central lesion. Furthermore, all malignant tumors and lymph nodes harbored the activating BRAF V600E mutation. The present case highlights various pathological features that support a mechanism of intraglandular spread, namely a strategic isthmic location of the primary tumor, radial pattern of distribution and extensive number of small malignant foci and BRAF mutational homogeneity.

Learning points:

  • Multifocal papillary thyroid carcinoma (PTC) is commonly seen in clinical practice, but the number of malignant foci is usually limited to ten or less.

  • There is no clear consensus in the literature as to whether multifocal PTC arises from a single or multiple distinct tumor progenitor cells.

  • Strategic location of the dominant tumor in the thyroid isthmus may favor intraglandular dissemination of malignant cells by means of the extensive lymphatic network.

  • An important pathological finding that may be suggestive of intrathyroidal metastatic spread is a central pattern of distribution with a reduction in the density of satellite lesions with increasing distance from the dominant focus.

  • PTCs originating from the isthmus with intraglandular metastatic dissemination behave more aggressively. As such, a more aggressive treatment course may be warranted, particularly with regard to the extent of surgery.

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

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.