Summary

Multiple endocrine neoplasia type 1 (MEN1) requires a high level of suspicion, and late diagnosis can lead to dire outcomes. Genetic counselling is an important part of management, with a lack of evidence surrounding an optimal approach in Aboriginal Australian populations. Our case surrounds a remote-dwelling 48-year-old Aboriginal Australian female who was reviewed by an inpatient endocrine team in 2020 for persistent hypercalcaemia on a background of a parathyroidectomy in 2011 for primary hyperparathyroidism (PHPT), while she was admitted to a local hospital for acute chronic abdominal pain. Relevant medical history included multiple pulmonary embolisms/deep vein thrombosis, myocardial infarction, atrial fibrillation, chronic thromboembolic pulmonary hypertension, right heart failure, human T-lymphotropic virus 1, recurrent abdominal pain, and gastro-oesophageal reflux disorder. Gastroscopies from 2013 and 2015 demonstrated chronic gastritis with hundreds of gastric polyps. Subsequent laboratory studies, neuroendocrine tumour (NET) screening, and CT imaging demonstrated a recurrence of PHPT and a new diagnosis of Zollinger–Ellison syndrome. A 68-gallium-DOTATATE PET/CT was in keeping with metastatic NET. Pituitary studies were normal. Genetic testing confirmed a rare heterozygous variant of c.207dupC in exon 2 of the MEN1 gene. Treatment was symptom based due to terminal comorbidities. Genetic counselling was attempted; however, cultural and logistical barriers were identified and the family declined further testing. Unfortunately, she died in 2021 from multifactorial respiratory failure. This case highlights the need for better approaches to genetic counselling systems for remote Aboriginal Australians and emphasizes the importance of early recognition and the challenges faced in remote areas in making such rare diagnoses.

Learning points

• Remote healthcare systems often lack access to adequate specialist care, resulting in delayed diagnosis of rare conditions and leading to morbidity and mortality.

• Further research and work need to be done to provide culturally appropriate genetic counselling systems in remote Aboriginal Australians.

• A high index of suspicion is required to diagnose MEN1.

• Consider MEN1 in any patient diagnosed with primary hyperparathyroidism, with age <40, and/or with the presence of multiglandular disease or with the presence of Zollinger–Ellison syndrome.

• MEN1 may be under-recognized in Aboriginal Australians.

Summary

X-linked hypophosphatemic rickets (XLH), the most prevalent form of inherited hypophosphatemic rickets, is caused by loss-of-function mutations in the gene encoding phosphate-regulating endopeptidase homolog, X-linked (PHEX). This case series presents 14 cases of XLH from Gulf Cooperation Council (GCC) countries. The patients’ medical history, biochemical and radiological investigative findings, as well as treatment responses and side effects from both conventional and burosumab therapy, are described. Cases were aged 2–40 years at diagnosis. There were two male cases and 12 female cases. All cases were treated with conventional therapy which resulted in a lack of improvement in or worsening of the clinical signs and symptoms of rickets or biochemical parameters. Side effects of conventional therapy included nausea, diarrhea, abdominal pain, nephrocalcinosis, and hyperparathyroidism, which affected the patients’ quality of life and adherence to treatment. In the 10 patients treated with burosumab, there was a marked improvement in the biochemical markers of rickets, with a mean increase in serum phosphate of +0.56 mmol/L and tubular maximum phosphate reabsorption (TmP) to glomerular filtration rate (GFR) ratio (TmP/GFR) of +0.39 mmol/L at 12 months compared to baseline. Furthermore, a mean decrease in serum alkaline phosphatase (ALP) of −80.80 IU/L and parathyroid hormone (PTH) of −63.61 pmol/L at 12 months compared to baseline was observed in these patients. Additionally, patients treated with burosumab reported reduced pain, muscle weakness, and fatigue as well as the ability to lead more physically active lives with no significant side effects of treatment.

Learning points

• Conventional therapy resulted in a suboptimal response, with a lack of improvement of clinical signs and symptoms.

• Side effects of conventional therapy included nausea, diarrhea, abdominal pain, nephrocalcinosis, and hyperparathyroidism, which affected the patients’ quality of life and adherence to treatment.

• Burosumab demonstrated marked improvements in the biochemical markers of rickets, in addition to reducing pain, muscle weakness, and fatigue.

• There were no significant side effects associated with burosumab therapy.

Summary

Iodine nutrition is a growing issue within the USA due to newer trends of non-iodized salts. There are no recent reviews looking at the current state of iodine deficiency-induced hypothyroidism in children in the USA. We performed a retrospective chart review at our tertiary pediatric endocrine clinic; four met the diagnostic criteria for iodine deficiency defined by a low urine iodine level. We further characterized severity of disease, risk factors, goiter, thyroid labs and antibodies. All cases had significant goiter and were diagnosed within the last 2 years. One case had iodine deficiency due to no iodized salt intake along with concurrent diagnosis of developmental delay and multiple food allergies, while others involved the use of non-iodized salts. Two cases had iodine deficiency along with autoimmunity. It is critical to obtain a dietary history for all patients who present with goiter and/or hypothyroidism. There may be a need to consider reevaluating current preventative measures for iodine deficiency, especially for certain vulnerable populations such as children who do not consume iodized salt.

Learning points

• In recent decades, iodine nutrition has become a growing concern due to changing dietary patterns and food manufacturing practices.

• A dietary history is crucial to obtain in children presenting with hypothyroidism and goiter, especially in children with restrictive diets due to behavioral concerns, developmental delays, or multiple food allergies.

• Of the 12 different types of salts commercially available, only table salt contains iodine in an appropriate amount; thus, individuals using specialty salts can develop mild to moderate iodine deficiency-related thyroid disease.

Summary

Carcinoid heart disease is a rare complication of carcinoid syndrome, resulting in right-sided valvular heart disease and subsequent heart failure due to long-term exposure to vasoactive substances. The management of this condition is complex, often requiring surgical intervention. Current perioperative regimens entail the use of prophylactic somatostatin analogs to prevent carcinoid crisis; however, regimens vary widely among practitioners and evidence supporting their efficacy in this clinical setting is mixed. This case report describes the perioperative management of a 65-year-old man with carcinoid heart disease requiring tricuspid and pulmonary valve replacement surgery. As an adjunct to somatostatin analog therapy, the novel tyrosine hydroxylase inhibitor, telotristat, was initiated preoperatively. This combination resulted in normalization of preoperative urinary 5-HIAA levels. The patient successfully underwent tricuspid and pulmonic valve replacement without evidence of carcinoid crisis. This clinical case is the first published documenting the use of telotristat in the perioperative period in a patient with carcinoid syndrome and carcinoid heart disease and was associated with a good long-term outcome despite the high-risk nature of the case.

Learning points

• Carcinoid crisis is a life-threatening complication of carcinoid syndrome, resulting in hemodynamic instability, bronchospasm, and arrhythmia.

• Cardiac surgical patients with carcinoid syndrome present a unique challenge as they are subject to physiologic conditions and medications which can potentiate intraoperative carcinoid crisis.

• Perioperative management of patients with carcinoid syndrome currently entails the use of prophylactic somatostatin analogs; however, these agents do not prevent carcinoid crisis in all cases.

• Telotristat, a tryptophan hydroxylase inhibitor, shows promise as an adjunctive therapy to somatostatin analogs to reduce the risk of intraoperative carcinoid crisis.

Summary

A 60-year-old woman presented to our clinic with an acute onset 3 months history of right ankle pain. The patient had a history of poorly differentiated thyroid cancer, which was treated with total thyroidectomy, left lateral neck dissection levels II–V and central neck dissection levels VI–VII followed by postoperative I-131 radioactive iodine (¹³¹I) ablation therapy 3.7 GBq 6 months ago. The post-¹³¹I WBS showed residual iodine-avid thyroid tissue with no other iodine-avid disease or metastasis. SPECT/CT of the neck and chest showed nonavid bilateral pulmonary nodules, discrete nodal masses in mediastinum and nonavid bone lesions. FDG-PET CT scan showed FDG-avid mediastinal lymph nodes (LN), innumerable non-FDG-avid subcentimetric pulmonary nodules and few FDG-avid lytic lesions in the skeleton. X-ray and MRI of the right ankle showed a well-marginated lytic lesion in the posterior body of calcaneus and 5 × 6 cm soft tissue mass lesion, respectively. The histopathology of the calcaneus mass confirmed a positive immunostaining for thyroid origin which includes thyroglobulin and TTF-1 with PAX-8. Endobronchial mediastinal and bronchial LN biopsy confirmed thyroid cancer metastasis. Gene mutation showed HRAS and GNA13 with a high tumor mutational burden. We describe a rare case of poorly differentiated thyroid cancer in a patient who presented with right ankle pain; we confirmed the cause to be a calcaneus metastasis from the thyroid cancer, with calcaneus being an extremely rare site for bone metastases. Gene mutations points toward treatment with immune checkpoint inhibitors.

Learning points

• Poorly differentiated thyroid carcinoma (PDTC) usually metastasizes to lung and bone but can rarely occur in the calcaneus.

• Patients with distant metastases have significantly worse long-term prognosis.

• Radiotherapy is effective in reducing the metastatic pains as well as reducing the size of the metastasis.

• PAX-8 staining can be used to differentiate thyroid carcinomas from lung adenocarcinomas.

• The importance of searching for gene mutations to decide the treatment of PDTC.

Summary

Bardet–Biedl syndrome (BBS) is a rare, autosomal recessive, multisystem non-motile ciliopathy of progressive onset. It is primarily characterised by rod–cone dystrophy, early-onset obesity and related complications, postaxial polydactyly, renal and genitourinary abnormalities, learning disabilities, and hypogonadism. The diagnosis is based on Beales’ modified diagnostic criteria. We present a case of two monozygotic female twins, 17 years of age at presentation, referred for obesity since childhood. The initial hormonal work-up was negative and no dysmorphic features were noted. They were diagnosed with exogenous obesity. However, after ophthalmologic problems became apparent, rod–cone dystrophy was observed and genetic testing was performed. A mutation in the BBS2 gene led to the diagnosis of BBS, although the full diagnostic criteria were not met. This case not only highlights the need to raise awareness for BBS but also exposes two limitations of the current diagnostic standard. The first limitation is the low sensitivity of the clinical diagnostic model, due to the progressive onset and the high variability of the syndrome. The second limitation is the unclear role of genetic testing. As genetic testing becomes more widely available, genetic diagnosis preceding clinical diagnosis will become more common, leading to a diagnostic conundrum. We propose an update of the diagnostic model. A less strict application in the presence of confirmed genetic mutations should be applied, as this could facilitate earlier diagnosis and intervention. This is important because therapeutic agents are being developed that could have a significant impact on quality of life and prognosis.

Learning points

• Due to the low prevalence, the significant inter-and intrafamilial variation, and the slowly evolving phenotype, monogenic forms of obesity such as Bardet–Biedl syndrome are difficult to diagnose. Despite advances in the understanding of the presentation, pathophysiology and access to accurate genetic characterisation, a substantial number of diagnoses are still made by ophthalmology, as recognition of BBS in other departments of medicine, remains limited.

• Clinical diagnosis of BBS is based on Beales’ modified diagnostic criteria which require the presence of four primary features or three primary features plus two secondary features. This model has its limitations. Due to the progressive onset of clinical symptoms, patients generally do not meet the diagnostic criteria early in life, leading to a delay in diagnosis. In addition, the role of genetic testing remains controversial. However, as it becomes more widely available, genetic diagnosis may precede a full clinical diagnosis.

• BBS has an impact on the quality of life and prognosis of both the patient and the family. Obesity management strategies are an important part of the multidisciplinary approach, as there is no cure available. Setmelanotide has shown promising results in a phase 3 trial, but its effect in clinical practice remains unproven.

Summary

There is a scarcity of literature relating to post-bariatric hypoglycaemia (PBH) in pregnancy. Recurrent hyperglycaemia and hypoglycaemia can have significant consequences for both the mother and the developing fetus. We describe a case of a young pregnant woman who was diagnosed with symptomatic PBH in the second trimester of pregnancy using continuous glucose monitoring (CGM) 3 years after Roux-en-Y gastric bypass (RYGB) surgery. Instigating a low glycaemic index and complex carbohydrate diet significantly improved the patient’s glycaemic excursions. Given that this condition is likely underdiagnosed as a complication of RYGB surgery, a greater awareness of this complication is needed. Patients should be adequately consented pre-operatively for this relatively frequent late surgical complication to enable patients to identify symptoms of this condition at an early stage and seek medical treatment.

Learning points

• PBH is an important diagnosis in patients post-RYGB surgery, particularly in women of childbearing age when consequences of both hyperglycaemia and hypoglycaemia during pregnancy can adversely affect both mother and the fetus.

• Adverse outcomes of recurrent hypoglycaemia to the fetus can include small for gestational age, intrauterine growth restriction and possible impairment of beta cell function.

• Providing adequate carbohydrate intake to allow growth of the fetus during pregnancy while also attempting to resolve both hyperglycaemia and hypoglycaemia associated with PBH by reducing the intake of simple carbohydrates and high glycaemic index foods can prove challenging.

• Patients should be adequately consented for late complications of RYGB surgery such as PBH in order to allow early recognition of symptoms and enable prompt treatment.

Summary

Endometrioid carcinomas of the ovary are a subtype of epithelial ovarian tumors, with sertoliform endometrioid carcinomas being a rare variant. We report a case of a previously healthy premenopausal woman presenting with androgenic symptoms in the form of hirsutism and male pattern alopecia. On further testing, she was found to have high levels of luteinizing hormone and total testosterone levels, and imaging revealed a large pelvic abdominal mass in the right ovary. She underwent total hysterectomy with bilateral salpingo-oophorectomy. Microscopy and histopathology confirmed the diagnosis of sertoliform endometrioid carcinoma. Her symptoms improved significantly on follow-up. Androgenic tumors might not be common in premenopausal women; however, it is important to maintain a high level of suspicion in patients presenting with virilizing symptoms especially of rapid progression.

Learning points

• Our 47-year-old patient presented with virilizing symptoms that were rapidly progressing, which raises the suspicion of an underlying androgen secreting neoplasm.

• Sertoliform endometrioid carcinoma (SEC) is an extremely rare variant of endometrioid carcinomas and tend to present at an earlier stage as compared to most endometrioid carcinomas of the ovary.

• Recognition of SEC in virilizing patients is important as it is a well-differentiated, low-grade malignancy with a good prognosis when confined to the ovary.

Summary

Neonatal hypoglycemia is a serious condition that can have a major impact on the growing neonatal brain. The differential diagnosis of neonatal hypoglycemia is broad and includes hyperinsulinism as well as panhypopituitarism. The FOXA2 gene has been involved in the development of the pancreas as well as the pituitary gland. Six cases have been reported thus far with FOXA2 mutations presenting with variable degrees of hypopituitarism, and only two patients had permanent hyperinsulinism; other cases have been reported with microdeletions in 20p11, the location that encompasses FOXA2, and those patients presented with a wider phenotype. A full-term female infant presented with severe hypoglycemia. Critical sampling showed an insulin of 1 mIU/mL, suppressed beta-hydroxybutyric acids, and suppressed free fatty acids. Blood glucose responded to glucagon administration. Growth hormone (GH) stimulation test later showed undetectable GH in all samples, and cortisol failed to respond appropriately to stimulation. Gonadotropins were undetectable at 1 month of life, and MRI showed ectopic posterior pituitary, interrupted stalk, hypoplastic anterior pituitary, cavum septum pellucidum, and diminutive appearance of optic nerves. Whole-exome sequencing revealed a likely pathogenic de novo c.604 T>C, p.Tyr202His FOXA2 mutation. We expand the known phenotype on FOXA2 mutations and report a likely pathogenic, novel mutation associated with hyperinsulinism and panhypopituitarism.

Learning points

• FOXA2 has been shown to play an important role in the neuroectodermal and endodermal development.

• FOXA2 mutation may lead to the rare combination of hyperinsulinism and panhypopituitarism.

• Patients reported so far all responded well to diazoxide. Dysmorphology may be subtle, and liver functions should be monitored.

Summary

A 55-year-old patient was admitted to our department for the management of a repetitive alteration of consciousness. Biological investigation results were consistent with endogenous hyperinsulinemic hypoglycemia. Insulinoma was therefore suspected. Abdominal computed tomography and endoscopic ultrasound showed no obvious pancreatic mass.Somatostatin receptor scintigraphy showed abnormal radioactive uptake in both the pancreatic tail and the uncinate process. Contrariwise, abdominal magnetic resonance imaging showed a unique lesion in the pancreas tail. The patient was then proposed for pancreatic surgery. Both intraoperative manual palpation and intraoperative ultrasonography of the pancreas showed a single corporal lesion of 1.5 cm. No lesion was found in the uncinate process. After a left pancreatectomy, the lesion was histopathologically confirmed to be a well-differentiated neuroendocrine tumor. The symptoms of the patient resolved almost immediately following the surgery. The follow-up is one and a half years to date.

Learning points

• The exact preoperative localization of the pancreatic mass remains the most challenging part of insulinoma diagnostic workup.

• The radiologist’s experience is the best warrantor to a precise localization of the tumor.

• ¹¹¹In-DTPA-octreotide uptake in the pancreatic uncinate process may be physiological and its interpretation must, therefore, be vigilant.

• Manual palpation along with intraoperative ultrasonography is considered as the most effective method for the localization of insulinomas during open surgery.