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Open access

Gemma White, Nicola Tufton and Scott A Akker

Summary

At least 40% of phaeochromocytomas and paraganglioma’s (PPGLs) are associated with an underlying genetic mutation. The understanding of the genetic landscape of these tumours has rapidly evolved, with 18 associated genes now identified. Among these, mutations in the subunits of succinate dehydrogenase complex (SDH) are the most common, causing around half of familial PPGL cases. Occurrence of PPGLs in carriers of SDHB, SDHC and SDHD subunit mutations has been long reported, but it is only recently that variants in the SDHA subunit have been linked to PPGL formation. Previously documented cases have, to our knowledge, only been found in isolated cases where pathogenic SDHA variants were identified retrospectively. We report the case of an asymptomatic suspected carotid body tumour found during surveillance screening in a 72-year-old female who is a known carrier of a germline SDHA pathogenic variant. To our knowledge, this is the first screen that detected PPGL found in a previously identified SDHA pathogenic variant carrier, during surveillance imaging. This finding supports the use of cascade genetic testing and surveillance screening in all carriers of a pathogenic SDHA variant.

Learning points:

  • SDH mutations are important causes of PPGL disease.

  • SDHA is much rarer compared to SDHB and SDHD mutations.

  • Pathogenicity and penetrance are yet to be fully determined in cases of SDHA-related PPGL.

  • Surveillance screening should be used for SDHA PPGL cases to identify recurrence, metastasis or metachronous disease.

  • Surveillance screening for SDH-related disease should be performed in identified carriers of a pathogenic SDHA variant.

Open access

Asma Deeb, Faisal Al-Zidgali and Bibian N Ofoegbu

Summary

Wolcott–Rallison syndrome (WRS) is a rare autosomal recessive disorder due to mutations in the EIF2AK3 gene. It is characterized by permanent neonatal diabetes mellitus, skeletal dysplasia, liver impairment, neutropenia and renal dysfunction. Liver is the most commonly affected organ and liver failure is the commonest cause of death in this syndrome. The EIF2AK3 gene encodes a transmembrane protein PERK, which is important for the cellular response to endoplasmic reticulum (ER) stress. The absence of PERK activity reduces the ER’s abilities to deal with stress, leading to cell death by apoptosis. On acquiring febrile illness, affected patients suffer from liver injury, which may progress into liver failure and death. Renal involvement is less common and is mainly in the form of functional renal impairment at the advanced stage of the disease. Structural renal anomalies have not been reported in WRS. We report a 6-month-old girl who presented with neonatal diabetes on day 1 of life. Her genetic testing confirmed WRS due to missense mutation in the EIF2AK3 gene (c.2867G > A, p.Gly956Glu). Parents are first-degree cousins and both are heterozygous carriers to the mutation. 2 paternal uncles had the same mutation and died of liver disease at 1 and 14 years of age. Neither had a renal disease. She presented with hematuria during a febrile illness at the age of 5 months. Ultrasound scan showed right ectopic multicystic dysplastic kidney (MCDK). To the best of our knowledge, this is the first patient with WRS who is reported to have an MCDK disease.

Learning points:

  • Neonatal diabetes should be considered in babies presenting with early hyperglycemia particularly if there is a family history.

  • Genetic diagnosis in neonatal diabetes enables disease confirmation, genetic counseling and anticipation of potential complications during concomitant situations such as acute illness, trauma or major surgery.

  • There is lack of phenotype–genotype correlation in Wolcott–Rallison syndrome.

  • Structural kidney abnormality, in our case MCDK, can be seen in WRS.

Open access

Pradeep Vasudevan, Corrina Powell, Adeline K Nicholas, Ian Scudamore, James Greening, Soo-Mi Park and Nadia Schoenmakers

Summary

In the absence of maternal thyroid disease or iodine deficiency, fetal goitre is rare and usually attributable to dyshormonogenesis, for which genetic ascertainment is not always undertaken in the UK. Mechanical complications include tracheal and oesophageal compression with resultant polyhydramnios, malpresentation at delivery and neonatal respiratory distress. We report an Indian kindred in which the proband (first-born son) had congenital hypothyroidism (CH) without obvious neonatal goitre. His mother’s second pregnancy was complicated by fetal hypothyroid goitre and polyhydramnios, prompting amniotic fluid drainage and intraamniotic therapy (with liothyronine, T3 and levothyroxine, T4). Sadly, intrauterine death occurred at 31 weeks. Genetic studies in the proband demonstrated compound heterozygous novel (c.5178delT, p.A1727Hfs*26) and previously described (c.7123G > A, p.G2375R) thyroglobulin (TG) mutations which are the likely cause of fetal goitre in the deceased sibling. TG mutations rarely cause fetal goitre, and management remains controversial due to the potential complications of intrauterine therapy however an amelioration in goitre size may be achieved with intraamniotic T4, and intraamniotic T3/T4 combination has achieved a favourable outcome in one case. A conservative approach, with surveillance, elective delivery and commencement of levothyroxine neonatally may also be justified, although intubation may be required post delivery for respiratory obstruction. Our observations highlight the lethality which may be associated with fetal goitre. Additionally, although this complication may recur in successive pregnancies, our case highlights the possibility of discordance for fetal goitre in siblings harbouring the same dyshormonogenesis-associated genetic mutations. Genetic ascertainment may facilitate prenatal diagnosis and assist management in familial cases.

Learning points:

  • CH due to biallelic, loss-of-function TG mutations is well-described and readily treatable in childhood however mechanical complications from associated fetal goitre may include polyhydramnios, neonatal respiratory compromise and neck hyperextension with dystocia complicating delivery.

  • CH due to TG mutations may manifest with variable phenotypes, even within the same kindred.

  • Treatment options for hypothyroid dyshormogenic fetal goitre in a euthyroid mother include intraamniotic thyroid hormone replacement in cases with polyhydramnios or significant tracheal obstruction. Alternatively, cases may be managed conservatively with radiological surveillance, elective delivery and neonatal levothyroxine treatment, although intubation and ventilation may be required to support neonatal respiratory compromise.

  • Genetic ascertainment in such kindreds may enable prenatal diagnosis and anticipatory planning for antenatal management of further affected offspring.

Open access

Nandini Shankara Narayana, Anne-Maree Kean, Lisa Ewans, Thomas Ohnesorg, Katie L Ayers, Geoff Watson, Arthur Vasilaras, Andrew H Sinclair, Stephen M Twigg and David J Handelsman

Summary

46,XX disorders of sexual development (DSDs) occur rarely and result from disruptions of the genetic pathways underlying gonadal development and differentiation. We present a case of a young phenotypic male with 46,XX SRY-negative ovotesticular DSD resulting from a duplication upstream of SOX9 presenting with a painful testicular mass resulting from ovulation into an ovotestis. We present a literature review of ovulation in phenotypic men and discuss the role of SRY and SOX9 in testicular development, including the role of SOX9 upstream enhancer region duplication in female-to-male sex reversal.

Learning points:

  • In mammals, the early gonad is bipotent and can differentiate into either a testis or an ovary. SRY is the master switch in testis determination, responsible for differentiation of the bipotent gonad into testis.

  • SRY activates SOX9 gene, SOX9 as a transcription factor is the second major gene involved in male sex determination. SOX9 drives the proliferation of Sertoli cells and activates AMH/MIS repressing the ovary. SOX9 is sufficient to induce testis formation and can substitute for SRY function.

  • Assessing karyotype and then determination of the presence or absence of Mullerian structures are necessary serial investigations in any case of DSD, except for mixed gonadal dysgenesis identified by karyotype alone.

  • Treatment is ideal in a multidisciplinary setting with considerations to genetic (implications to family and reproductive recurrence risk), psychological aspects (sensitive individualized counseling including patient gender identity and preference), endocrinological (hormone replacement), surgical (cosmetic, prophylactic gonadectomy) fertility preservation and reproductive opportunities and metabolic health (cardiovascular and bones).

Open access

Athanasios Fountas, Zoe Giotaki, Evangelia Dounousi, George Liapis, Alexandra Bargiota, Agathocles Tsatsoulis and Stelios Tigas

Summary

Proteinuric renal disease is prevalent in congenital or acquired forms of generalized lipodystrophy. In contrast, an association between familial partial lipodystrophy (FPLD) and renal disease has been documented in very few cases. A 22-year-old female patient presented with impaired glucose tolerance, hyperinsulinemia, hirsutism and oligomenorrhea. On examination, there was partial loss of subcutaneous adipose tissue in the face, upper and lower limbs, bird-like facies with micrognathia and low set ears and mild acanthosis nigricans. Laboratory investigations revealed hyperandrogenism, hyperlipidemia, elevated serum creatine kinase and mild proteinuria. A clinical diagnosis of FPLD of the non-Dunnigan variety was made; genetic testing revealed a heterozygous c.1045C > T mutation in exon 6 of the LMNA gene, predicted to result in an abnormal LMNA protein (p.R349W). Electromyography and muscle biopsy were suggestive of non-specific myopathy. Treatment with metformin and later with pioglitazone was initiated. Due to worsening proteinuria, a renal biopsy was performed; histological findings were consistent with mild focal glomerular mesangioproliferative changes, and the patient was started on angiotensin-converting enzyme inhibitor therapy. This is the fourth report of FPLD associated with the c.1045C > T missense LMNA mutation and the second with co-existent proteinuric renal disease. Patients carrying this specific mutation may exhibit a phenotype that includes partial lipodystrophy, proteinuric nephropathy, cardiomyopathy and atypical myopathy.

Learning points:

  • Lipodystrophy is a rare disorder characterized by the complete or partial loss of subcutaneous adipose tissue, insulin resistance, diabetes mellitus and hyperlipidemia.

  • Proteinuric renal disease is a prevalent feature of generalized lipodystrophy but rare in familial partial lipodystrophy.

  • Patients carrying the c.1045C > T missense LMNA mutation (p.R349W) may present with familial partial lipodystrophy, proteinuric nephropathy, cardiomyopathy and atypical myopathy.

Open access

S A A van den Berg, N E van ‘t Veer, J M A Emmen and R H T van Beek

Summary

We present a case of iatrogenic Cushing’s syndrome, induced by treatment with fluticasone furoate (1–2 dd, 27.5 µg in each nostril) in a pediatric patient treated for congenital HIV. The pediatric patient described in this case report is a young girl of African descent, treated for congenital HIV with a combination therapy of Lopinavir/Ritonavir (1 dd 320/80 mg), Lamivudine (1 dd 160 mg) and Abacavir (1 dd 320 mg). Our pediatric patient presented with typical Cushingoid features (i.e. striae of the upper legs, full moon face, increased body and facial hair) within weeks after starting fluticasone furoate therapy, which was exacerbated after increasing the dose to 2 dd because of complaints of unresolved rhinitis. Biochemical analysis fitted iatrogenic Cushing’s syndrome, with a repeatedly low cortisol (<0.03 µM, ref 0.14–0.60 µM) and low ACTH (9 pg/mL, ref 9–52 pg/mL) without signs of adrenal insufficiency. No other biochemical abnormalities that could point to adrenal or pituitary dysfunction were detected; electrolytes, thyroid and gonadal function, and IGF-1 were within the normal range. Pharmacogenetic analysis revealed that the pediatric patient carried the CYP3A4 *1B/*1G and CYP3A5 *3/*3 genotype (associated with a partial and complete loss of enzyme activity, respectively) which is associated with the development of iatrogenic Cushing’s syndrome in patients treated for HIV due to the strong inhibition of CYP3 enzymes by Ritonavir. Upon discontinuation of fluticasone treatment, the pediatric patient improved both clinically and biochemically with normalisation of cortisol and ACTH within a couple of weeks.

Learning points:

  • Fluticasone therapy may induce iatrogenic Cushing’s syndrome in a patient treated with anti-retroviral therapy.

  • Pharmacogenetic analysis, in particular CYP3A genotyping, provides useful information in patients treated for HIV with respect to possible future steroid treatment.

  • Fluticasone furoate is not detected in the Siemens Immulite cortisol binding assay.

Open access

Teresa Rego, Fernando Fonseca, Stéphanie Espiard, Karine Perlemoine, Jérôme Bertherat and Ana Agapito

Summary

PBMAH is a rare etiology of Cushing syndrome (CS). Familial clustering suggested a genetic cause that was recently confirmed, after identification of inactivating germline mutations in armadillo repeat-containing 5 (ARMC5) gene. A 70-year-old female patient was admitted due to left femoral neck fracture in May 2014, in Orthopedics Department. During hospitalization, hypertension (HTA) and hypokalemia were diagnosed. She presented with clinical signs of hypercortisolism and was transferred to the Endocrinology ward for suspected CS. Laboratory workup revealed: ACTH <5 pg/mL; urinary free cortisol (UFC), 532 µg/24 h (normal range: 20–90); failure to suppress the low-dose dexamethasone test (0.5 mg every 6 h for 48 h): cortisol 21 µg/dL. Abdominal magnetic resonance imaging (MRI) showed enlarged nodular adrenals (right, 55 × 54 × 30 mm; left, 85 × 53 × 35 mm), and she was submitted to bilateral adrenalectomy. In 2006, this patient’s 39-year-old daughter had been treated by one of the authors. She presented with severe clinical and biological hypercortisolism. Computed tomography (CT) scan showed massively enlarged nodular adrenals with maximal axis of 15 cm for both. Bilateral adrenalectomy was performed. In this familial context of PBMAH, genetic study was performed. Leucocyte DNA genotyping identified in both patients the same germline heterozygous ARMC5 mutation in exon 1 c.172_173insA p.I58Nfs*45. The clinical cases herein described have an identical phenotype with severe hypercortisolism and huge adrenal glands, but different ages at the time of diagnosis. Current knowledge of inheritance of this disease, its insidious nature and the well-known deleterious effect of hypercortisolism favor genetic study to timely identify and treat these patients.

Learning points:

  • PBMAH is a rare etiology of CS, characterized by functioning adrenal macronodules and variable cortisol secretion.

  • The asymmetric/asynchronous involvement of only one adrenal gland can also occur, making disease diagnosis a challenge.

  • Familial clustering suggests a genetic cause that was recently confirmed, after identification of inactivating germline mutations in armadillo repeat-containing 5 (ARMC5) gene.

  • The insidious nature of this disease and the well-known deleterious effect of hypercortisolism favor genetic study of other family members, to diagnose and treat these patients timely.

  • As ARMC5 is expressed in many organs and recent findings suggest an association of PBMAH and meningioma, a watchful follow-up is required.

Open access

Durgesh Prasad Chaudhary, Tshristi Rijal, Kunal Kishor Jha and Harpreet Saluja

Summary

Combined pituitary hormonal deficiency (CPHD) is a rare disease that results from mutations in genes coding for transcription factors that regulate the differentiation of pituitary cells. PROP1 gene mutations are one of the etiological diagnoses of congenital panhypopituitarism, however symptoms vary depending on phenotypic expression. We present a case of psychosis in a 36-year-old female with congenital panhypopituitarism who presented with paranoia, flat affect and ideas of reference without a delirious mental state, which resolved with hormone replacement and antipsychotics. Further evaluation revealed that she had a homozygous mutation of PROP1 gene. In summary, compliance with hormonal therapy for patients with hypopituitarism appears to be effective for the prevention and treatment of acute psychosis symptoms.

Learning points:

  • Patients with PROP1 gene mutation may present with psychosis with no impairment in orientation and memory.

  • There is currently inadequate literature on this topic, and further study on the possible mechanisms of psychosis as a result of endocrine disturbance is required.

  • Compliance with hormonal therapy for patients with hypopituitarism appears to be effective for prevention and treatment of acute psychosis symptoms.

Open access

Whitney L Stuard, Bryan K Gallerson and Danielle M Robertson

Summary

The use of in vivo confocal microscopy (IVCM) is rapidly emerging as an important clinical tool to evaluate changes in corneal sensory nerves as a surrogate measure for diabetic peripheral neuropathy. Commonly used metrics to document and grade the severity of diabetes and risk for diabetic peripheral neuropathy include nerve fiber length, density, branching and tortuosity. In addition to corneal nerves, thinning of the retinal fiber layer has been shown to correlate with the severity of diabetic disease. Here, we present a case report on a pre-diabetic 60-year-old native American woman with abnormal corneal nerve morphology and retinal nerve fiber layer thinning. Her past medical history was positive for illicit substance abuse. IVCM showed a decrease in nerve fiber density and length, in addition to abnormally high levels of tortuosity. OCT revealed focal areas of reduced retinal nerve fiber layer thickness that were asymmetric between eyes. This is the first report of abnormally high levels of tortuosity in the corneal sub-basal nerve plexus in a patient with a past history of cocaine abuse. It also demonstrates, for the first time, that illicit substance abuse can have long-term adverse effects on ocular nerves for years following discontinued use of the drug. Studies using IVCM to evaluate changes in corneal nerve morphology in patients with diabetes need to consider a past history of illicit drug use as an exclusionary measure.

Learning points:

  • Multiple ocular and systemic factors can impede accurate assessment of the corneal sub-basal nerve plexus by IVCM in diabetes.

  • Although current history was negative for illicit substance abuse, past history can have longstanding effects on corneal nerves and the retinal nerve fiber layer.

  • Illicit drug use must be considered an exclusionary measure when evaluating diabetes-induced changes in corneal nerve morphology and the retinal nerve fiber layer.

Open access

Liudmila Rozhinskaya, Ekaterina Pigarova, Ekaterina Sabanova, Elizaveta Mamedova, Iya Voronkova, Julia Krupinova, Larisa Dzeranova, Anatoly Tiulpakov, Vera Gorbunova, Nadezhda Orel, Artur Zalian, Galina Melnichenko and Ivan Dedov

Summary

Parathyroid carcinoma is an extremely rare disorder with little treatment options. It could be misdiagnosed in medical centers with little experience in management of such cases. Our clinical case shows that the initial misdiagnosis of a parathyroid carcinoma in a young woman has led to the development of multiple lung metastases, thus making its treatment hardly possible. Initiation of treatment with sorafenib – a multi-kinase inhibitor approved for treatment of different types of cancer but not parathyroid carcinoma – has led to a significant decrease in the size of lung metastases and has prevented the progression of hyperparathyroidism, which is usually severe in cases of parathyroid carcinoma. The detection of a germline CDC73 mutation in this patient has raised additional concerns about the necessity of periodic screening for early detection of renal, jaw and uterine lesions.

Learning points:

  • Diagnosis of parathyroid carcinoma may be challenging due to the absence of reliable diagnostic criteria. Thus, thorough histological examination is needed using immunohistochemical staining of resected tissue in suspicious cases.

  • CDC73 genetic testing should be considered in patients with parathyroid carcinoma.

  • Sorafenib may be a promising treatment of patients with parathyroid carcinoma with distant metastases.