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Open access

Aoife Garrahy, Matilde Bettina Mijares Zamuner and Maria M Byrne

Summary

Coexistence of autoimmune diabetes and maturity-onset diabetes of the young (MODY) is rare. We report the first case of coexisting latent autoimmune diabetes of adulthood (LADA) and glucokinase (GCK) MODY. A 32-year-old woman was treated with insulin for gestational diabetes at age 32 years; post-partum, her fasting blood glucose was 6.0 mmol/L and 2-h glucose was 11.8 mmol/L following an oral glucose tolerance test, and she was maintained on diet alone. Five years later, a diagnosis of LADA was made when she presented with fasting blood glucose of 20.3 mmol/L and HbA1C 125 mmol/mol (13.6%). GCK-MODY was identified 14 years later when genetic testing was prompted by identification of a mutation in her cousin. Despite multiple daily insulin injections her glycaemic control remained above target and her clinical course has been complicated by multiple episodes of hypoglycaemia with unawareness. Although rare, coexistence of latent autoimmune diabetes of adulthood and monogenic diabetes should be considered if there is a strong clinical suspicion, for example, family history. Hypoglycaemic unawareness developed secondary to frequent episodes of hypoglycaemia using standard glycaemic targets for LADA. This case highlights the importance of setting fasting glucose targets within the expected range for GCK-MODY in subjects with coexisting LADA.

Learning points:

  • We report the first case of coexisting latent autoimmune diabetes of adulthood (LADA) and GCK-MODY.

  • It has been suggested that mutations in GCK may lead to altered counter-regulation and recognition of hypoglycaemia at higher blood glucose levels than patients without such mutation. However, in our case, hypoglycaemic unawareness developed secondary to frequent episodes of hypoglycaemia using standard glycaemic targets for LADA.

  • This case highlights the importance of setting fasting glucose targets within the expected range for GCK-MODY in subjects with coexisting LADA to avoid hypoglycaemia.

Open access

Akihiko Ando, Shoichiro Nagasaka and Shun Ishibashi

Summary

We report a case of a woman with diabetes mellitus caused by a genetic defect in ABCC8-coding sulfonylurea receptor 1 (SUR1), a subunit of the ATP-sensitive potassium (KATP) channel protein. She was diagnosed with diabetes at 7 days after birth. After intravenous insulin drip for 1 month, her hyperglycaemia remitted. At the age of 13 years, her diabetes relapsed, and after that she had been treated by intensive insulin therapy for 25 years with relatively poor glycaemic control. She was switched to oral sulfonylurea therapy and attained euglycaemia. In addition, her insulin secretory capacity was ameliorated gradually.

Learning points:

  • Genetic testing should be considered in any individuals or family with diabetes that occurred within the first year or so of life.

  • Sulfonylurea can achieve good glycaemic control in patients with KATP channel mutations by restoring endogenous insulin secretion, even if they were treated with insulin for decades.

  • Early screening and genetic testing are important to improve the prognosis of patients with neonatal diabetes mellitus arising from ABCC8 or KCNJ11 mutation.

Open access

Naoya Toriu, Masayuki Yamanouchi, Rikako Hiramatsu, Noriko Hayami, Junichi Hoshino, Akinari Sekine, Masahiro Kawada, Eiko Hasegawa, Tatsuya Suwabe, Keiichi Sumida, Toshiharu Ueno, Naoki Sawa, Kenichi Ohashi, Takeshi Fujii, Kenmei Takaichi, Motoko Yanagita, Tetsuro Kobayasi and Yoshifumi Ubara

Summary

We report the case of a 67-year-old Japanese woman with type 1 diabetes mellitus. At 47 years of age, her hemoglobin A1c (HbA1c) was 10.0%, and she had overt nephropathy. The first renal biopsy yielded a diagnosis of diabetic nephropathy. Intensive glycemic control was initiated and her HbA1c improved to 6.0%. Renal dysfunction showed no progression for 15 years. At 62 years of age, a second renal biopsy was performed. Glomerular lesions did not show progression but tubulointerstitial fibrosis and vascular lesions showed progression compared with the first biopsy. Intensive glycemic control can prevent the progression of glomerular lesions, but might not be effective for interstitial and vascular lesions.

Learning points:

  • Intensive control of blood glucose can prevent the progression of glomerular lesions.

  • Intensive control of blood glucose may not be able to prevent progression of interstitial and vascular lesions.

  • CSII reduces HbA1c without increasing the risk of hypoglycemia.

Open access

W K M G Amarawardena, K D Liyanarachchi, J D C Newell-Price, R J M Ross, D Iacovazzo and M Debono

Summary

The granulation pattern of somatotroph adenomas is well known to be associated with differing clinical and biochemical characteristics, and it has been shown that sparsely granulated tumours respond poorly to commonly used somatostatin receptor ligands (SRLs). We report a challenging case of acromegaly with a sparsely granulated tumour resistant to multiple modalities of treatment, ultimately achieving biochemical control with pasireotide. A 26-year-old lady presented with classical features of acromegaly, which was confirmed by an oral glucose tolerance test. Insulin-like growth factor 1 (IGF1) was 1710 µg/L (103–310 µg/L) and mean growth hormone (GH) was >600 U/L. MRI scan showed a 4 cm pituitary macroadenoma with suprasellar extension and right-sided cavernous sinus invasion. She underwent trans-sphenoidal pituitary surgery. Histology displayed moderate amounts of sparsely granular eosinophilic cytoplasm, staining only for GH. Postoperative investigations showed uncontrolled disease (IGF1:1474 µg/L, mean GH:228 U/L) and residual tumour in the cavernous sinus. She received external beam fractionated radiation. Over the years, she received octreotide LAR (up to 30 mg), lanreotide (up to 120 mg) two weekly, cabergoline, pegvisomant and stereotactic radiosurgery to no avail. Only pegvisomant resulted in an element of disease control; however, this had to be stopped due to abnormal liver function tests. Fifteen years after the diagnosis, she was started on pasireotide 40 mg monthly. Within a month, her IGF1 dropped and has remained within the normal range (103–310 µg/L). Pasireotide has been well tolerated, and there has been significant clinical improvement. Somatostatin receptor subtyping revealed a positivity score of two for both sst5 and sst2a subtypes.

Learning points:

  • Age, size of the tumour, GH levels on presentation, histopathological type and the somatostatin receptor status of the tumour in acromegaly should be reviewed in patients who poorly respond to first-generation somatostatin receptor ligands.

  • Tumours that respond poorly to first-generation somatostatin receptor ligands, especially sparsely granulated somatotroph adenomas, can respond to pasireotide and treatment should be considered early in the management of resistant tumours.

  • Patients with membranous expression of sst5 are likely to be more responsive to pasireotide.

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

Cristina Alvarez-Escola and Jersy Cardenas-Salas

Summary

In patients with active acromegaly after pituitary surgery, somatostatin analogues are effective in controlling the disease and can even be curative in some cases. After treatment discontinuation, the likelihood of disease recurrence is high. However, a small subset of patients remains symptom-free after discontinuation, with normalized growth hormone (GH) and insulin-like growth factor (IGF1) levels. The characteristics of patients most likely to achieve sustained remission after treatment discontinuation are not well understood, although limited evidence suggests that sustained remission is more likely in patients with lower GH and IGF1 levels before treatment withdrawal, in those who respond well to low-dose treatment, in those without evidence of adenoma on an MRI scan and/or in patients who receive long-term treatment. In this report, we describe the case of a 56-year-old female patient treated with lanreotide Autogel for 11 years. Treatment was successfully discontinued, and the patient is currently disease-free on all relevant parameters (clinical, biochemical and tumour status). The successful outcome in this case adds to the small body of literature suggesting that some well-selected patients who receive long-term treatment with somatostatin analogues may achieve sustained remission.

Learning points:

  • The probability of disease recurrence is high after discontinuation of treatment with somatostatin analogues.

  • Current data indicate that remission after treatment discontinuation may be more likely in patients with low GH and IGF1 levels before treatment withdrawal, in those who respond well to low-dose treatment, in those without evidence of adenoma on MRI, and/or in patients receiving prolonged treatment.

  • This case report suggests that prolonged treatment with somatostatin analogues can be curative in carefully selected patients.

Open access

Taiba Zornitzki, Hadara Rubinfeld, Lyudmila Lysyy, Tal Schiller, Véronique Raverot, Ilan Shimon and Hilla Knobler

Summary

Acromegaly due to ectopic GHRH secretion from a neuroendocrine tumor (NET) is rare and comprises <1% of all acromegaly cases. Herein we present a 57-year-old woman with clinical and biochemical features of acromegaly and a 6 cm pancreatic NET (pNET), secreting GHRH and calcitonin. Following surgical resection of the pancreatic tumor, IGF1, GH and calcitonin normalized, and the clinical features of acromegaly improved. In vitro studies confirmed that the tumor secreted large amounts of both GHRH and calcitonin, and incubation of pNET culture-derived conditioned media stimulated GH release from a cultured human pituitary adenoma. This is a unique case of pNET secreting both GHRH and calcitonin. The ability of the pNET-derived medium to stimulate in vitro GH release from a human pituitary-cell culture, combined with the clinical and hormonal remission following tumor resection, confirmed the ectopic source of acromegaly in this patient.

Learning points

  • Signs, symptoms and initial work-up of acromegaly due to ectopic GHRH secretion are similar to pituitary-dependent acromegaly. However, if no identifiable pituitary lesion is found, somatostatin receptor scan and further imaging (CT, MRI) should be performed.

  • Detection of GHRH in the blood and in the tumor-derived medium supports the diagnosis of ectopic GHRH secretion.

  • Functional bioactivity of pNET-secreted GHRH can be proved in vitro by releasing GH from human pituitary cells.

Open access

C Mumby, J R E Davis, J Trouillas and C E Higham

Summary

A 52-year-old lady was referred after a 5 cm left adrenal mass was detected on computed tomography (CT) scanning. She was asymptomatic although was noted to have acromegalic facies. Blood pressure (BP) was normal but plasma normetanephrines were raised to 2.81 mmol/l (<1.09) and urinary normetadrenaline excretion 5.3 μmol/24 h (0–4.3). Adrenal biochemistry screen was otherwise normal. Metaiodobenzylguanidine (MIBG) scan demonstrated uptake in the adrenal lesion. Growth hormone (GH) nadir on oral glucose tolerance test (OGTT) was 2.2 ng/ml with an elevated IGF1 level of 435 ng/ml (72–215), confirming acromegaly biochemically. The remainder of the pituitary screen was normal. A magnetic resonance imaging (MRI) scan of the pituitary revealed an enlarged pituitary gland with a microadenoma/cyst of 2–3 mm in diameter. Alpha blockade was achieved with a titrated dose of phenoxybenzamine before a successful laparoscopic hand-assisted left adrenalectomy. Postoperative biochemical testing revealed a normal plasma normetanephrine level of 0.6 nmol/l (<1.09) and a metanephrine level of 0.35 nmol/l (<0.46 nmol/l). Nadir on OGTT was normal at 0.07 ng/ml with an IGF1 level within the reference range at 111 ng/ml (75–215). Histology demonstrated a well-circumscribed and encapsulated oval mass with microscopic features typical for a phaeochromocytoma. The sections stained strongly positive for GHRH in 20% of cells on immunocytochemistry. Genetic analysis showed no pathogenic mutation. This is a report of the rare condition of a phaeochromocytoma co-secreting GHRH resulting in clinical and biochemical acromegaly. Neuroendocrine tumours can stain positive for GHRH without coexisting acromegaly, but the resolution of patient symptoms and normalisation of serum GH and IGF1 levels following surgery imply that this was functional secretion. Pituitary surgery should be avoided in such cases.

Learning points

  • Incidental findings on imaging require thorough investigation to determine the presence of serious pathology.

  • Acromegaly and phaeochromocytoma are rarely coincident in the same patient. If this occurs, co-secretion of GHRH from the phaeochromocytoma or the presence of underlying genetic abnormalities must be considered.

  • Acromegaly is due to ectopic GHRH-secreting neuroendocrine tumours in <1% of cases, most commonly pancreatic or bronchial lesions.

  • Co-secretion of GHRH from a phaeochromocytoma is extremely rare.

  • In such cases, the pituitary gland may appear enlarged but pituitary surgery should be avoided and surgical treatment of the neuroendocrine tumour attempted.

Open access

Hiromi Himuro, Takashi Sugiyama, Hidekazu Nishigori, Masatoshi Saito, Satoru Nagase, Junichi Sugawara and Nobuo Yaegashi

Summary

Diabetic ketoacidosis (DKA) during pregnancy is a serious complication in both mother and fetus. Most incidences occur during late pregnancy in women with type 1 diabetes mellitus. We report the rare case of a woman with type 1 diabetes mellitus who had normal glucose tolerance during the first trimester but developed DKA during late pregnancy. Although she had initially tested positive for screening of gestational diabetes mellitus during the first trimester, subsequent diagnostic 75-g oral glucose tolerance tests showed normal glucose tolerance. She developed DKA with severe general fatigue in late pregnancy. The patient's general condition improved after treatment for ketoacidosis, and she vaginally delivered a healthy infant at term. The presence of DKA caused by the onset of diabetes should be considered, even if the patient shows normal glucose tolerance during the first trimester.

Learning points

  • The presence of DKA caused by the onset of diabetes should be considered, even if the patient shows normal glucose tolerance during the first trimester.

  • Symptoms including severe general fatigue, nausea, and weight loss are important signs to suspect DKA. Findings such as Kussmaul breathing with ketotic odor are also typical.

  • Urinary test, atrial gas analysis, and anion gap are important. If pH shows normal value, calculation of anion gap is important. If the value of anion gap is more than 12, a practitioner should consider the presence of metabolic acidosis.

Open access

Ramez Ibrahim, Atul Kalhan, Alistair Lammie, Christine Kotonya, Ravindra Nannapanenni and Aled Rees

Summary

A 30-year-old female presented with a history of secondary amenorrhoea, acromegalic features and progressive visual deterioration. She had elevated serum IGF1 levels and unsuppressed GH levels after an oral glucose tolerance test. Magnetic resonance imaging revealed a heterogeneously enhancing space-occupying lesion with atypical extensive calcification within the sellar and suprasellar areas. Owing to the extent of calcification, the tumour was a surgical challenge. Postoperatively, there was clinical, radiological and biochemical evidence of residual disease, which required treatment with a somatostatin analogue and radiotherapy. Mutational analysis of the aryl hydrocarbon receptor-interacting protein (AIP) gene was negative. This case confirms the relatively rare occurrence of calcification within a pituitary macroadenoma and its associated management problems. The presentation, biochemical, radiological and pathological findings are discussed in the context of the relevant literature.

Learning points

  • Calcification of pituitary tumours is relatively rare.

  • Recognising calcification in pituitary adenomas on preoperative imaging is important in surgical decision-making.

  • Gross total resection can be difficult to achieve in the presence of extensive calcification and dictates further management and follow-up to achieve disease control.