Summary

Familial renal glucosuria (FRG) is a rare renal tubular disorder characterized by increased urinary glucose excretion despite normoglycemia. It is most commonly caused by pathogenic variants in the solute carrier family V member 2 (SLC5A2) gene. This gene encodes the sodium–glucose cotransporter 2, crucial for glucose reabsorption. We report the case of a 44-year-old male referred to the endocrinology outpatient clinic for unexplained glucosuria despite well-controlled diabetes mellitus with metformin and gliclazide therapy. His main complaints were nocturia and an unintentional 5 kg weight loss in 1 year. A 24-h urinary collection revealed overt glucosuria (23.3 g/1.73 m²/24 h), generalized aminoaciduria, and increased uric acid excretion (fractional excretion: 6.4%). Whole-exome sequencing revealed a novel heterozygous c.469-1G>A likely pathogenic variant in the SLC5A2 gene. Specific analysis of the maturity-onset diabetes of the young type (MODY) gene panel showed no pathogenic variants in the hepatocyte nuclear factor-1A (HNF-1A; MODY3) nor in other MODY-associated genes. We assume that the association of glucosuria, aminoaciduria, and increased uric acid excretion can be explained by the combination of diabetes and the likely pathogenic SLC5A2 variant in this patient. In conclusion, we describe a well-controlled diabetic patient with FRG, associated with a novel heterozygous c.469-1G>A likely pathogenic variant in the SLC5A2 gene.

Learning points

• The diagnosis of a renal tubular disorder should be considered in patients with unexplained glucosuria and diabetes mellitus, especially if the latter is well controlled.

• FRG usually presents with glucosuria but may be associated with generalized aminoaciduria and hyperuricosuria.

• Genetic analysis should be considered in patients with young-onset diabetes and glucosuria, particularly with a positive family history.

Summary

Thyroid storm is a clinical diagnosis characterized by life-threatening multisystemic organ involvement in the setting of uncontrolled hyperthyroidism. Current estimates suggest a mortality rate of up to 30%. Treatment often consists of the administration of thionamide medications, iodine solution(s), corticosteroids, and beta-blockers; in extreme circumstances, both plasmapheresis and thyroidectomy are subsequent therapeutic options. Thionamides are typically administered orally, with the intent of preventing further thyroid hormone synthesis; however, in the literature, there are instances whereby oral access cannot be obtained, and alternative routes of administration are required. We present a case of a patient who presented with a thyroid storm due to lack of adherence to methimazole. During admission, he was found to have significant abdominal pain and ultimately a duodenal perforation requiring strict nil-per-os (NPO) status, due to which he was unable to receive oral thionamides. Due to the lack of availability of intravenous formulations of thionamides in the United States, this patient was treated with an enema compound of propylthiouracil for a total of five per rectum (PR) doses. He would later develop hepatocellular injury, requiring discontinuation and eventual transition to oral methimazole. The literature pertaining to alternative-route thionamide administration is scant, and therefore this case report and literature review is written to provide an up-to-date review and further educate all levels of clinicians about this infrequent (but emergent) situation.

Learning points

• Thyroid storm is a clinical diagnosis for which urgent recognition is required to prevent untoward mortality.

• Treatment for thyroid storm requires prompt administration of thionamides, iodine, corticosteroids, and beta-blockers. In extreme circumstances, treatment considerations include plasmapheresis and thyroidectomy.

• Infrequently, patients with a thyroid storm may not be able to tolerate oral medications, for which alternative routes of access are required.

• Currently, available alternatives include intravenous methimazole (in Europe and Japan), as well as both enema and suppository preparations of propylthiouracil and methimazole.

Summary

Thyroid-stimulating hormone-secreting pituitary adenomas (TSHomas) are rare, accounting for less than 1% of all pituitary adenomas. We present a case of hyperthyroidism secondary to a likely TSHoma and coexisting functional thyroid adenoma. Laboratory errors and familial abnormalities in thyroid function tests were ruled out, and a diagnosis of the toxic thyroid adenoma was confirmed on a thyroid uptake scan. However, the triiodothyronine suppression test was contraindicated due to the patient’s cardiovascular disease, and the thyrotropin-releasing hormone stimulation test, measurement of glycoprotein hormone alpha-subunit, and genetic testing were unavailable. Magnetic resonance imaging of the brain revealed a suprasellar pituitary macroadenoma measuring 40 mm × 20.3 mm × 17 mm. The patient was initiated on carbimazole; however, thyroid stimulating hormone and thyroxine levels remained elevated. The patient declined trans-sphenoidal surgery and was treated with radioactive iodine to manage the toxic thyroid adenoma, leading to reduced thyroxine levels and symptom improvement. Unfortunately, the patient passed away before long-acting somatostatin analogs became available. This case highlights the diagnostic and therapeutic challenges involved in managing thyrotoxicosis with dual etiology.

Learning points

• Hyperthyroidism can have multiple etiologies, which can coexist in the same patient.

• Persistent discordant thyroid function tests warrant further investigation.

• The gold standard for diagnosis of TSHomas remains immunohistochemical analysis of the tumor tissue.

Summary

Neonatal adrenal hemorrhage (NAH) occurs in up to 3% of infants and is the most common adrenal mass in newborns. The most common presentation of NAH is an asymptomatic palpable flank mass which resolves over time without intervention. In rare cases, NAH can present as hemorrhage, shock, or adrenal insufficiency. This case describes a preterm infant born with severe anemia in the setting of bilateral adrenal hemorrhages with resulting adrenal insufficiency. The infant was successfully treated with blood transfusions and steroids. This is a unique presentation of NAH as it was bilateral, presented with severe anemia, and resulted in prolonged adrenal insufficiency.

Learning points

• Consider adrenal hemorrhage for cases of severe anemia at birth.

• Adrenal insufficiency is a rare complication of adrenal hemorrhage.

• Adrenal recovery can take months, if not years.

Summary

Thyroid cancer is one of the most common manifestations of Cowden syndrome, yet the syndrome is rare. The incidence of Cowden syndrome is 1 in 200,000. The diagnosis can be made clinically when patients present with a combination of symptoms such as mucocutaneous lesions with a strong personal or family history of thyroid, breast, endometrial, and colorectal cancer. A high index of suspicion is required to provide a clinical diagnosis utilizing major and minor criteria. Once a clinical diagnosis is made, genetic testing for a PTEN mutation, a tumor suppressor gene, is recommended. Cancer surveillance should be performed for those with positive genetic testing as well as those with negative genetic testing who still meet clinical diagnostic criteria. We present two cases of Cowden syndrome: one case involving an increasing number of thyroid nodules in a patient with known Cowden syndrome and another patient with a strong family history of cancer, personal history of follicular thyroid cancer, and numerous colonic polyps on screening colonoscopy. These cases demonstrate how early diagnosis of Cowden syndrome can help detect early cancer in both the patient and affected relatives.

Learning points

• Diagnosing Cowden syndrome helps pre-risk stratification for early cancer screening.

• The diagnosis of Cowden syndrome can be made with a combination of major and minor criteria: any two major criteria with or without a minor criterion; one major and one minor criterion; or three minor criteria.

• Patients who meet the diagnostic criteria for Cowden syndrome should undergo genetic screening.

Summary

Dumping syndrome is a rare but potentially serious condition that causes inappropriate postprandial hyperinsulinemia leading to hypoglycemia in children following gastrointestinal surgeries. While dietary modifications are often the first line of treatment, severe cases may require pharmacological intervention to prevent severe hypoglycemia. We present a case of successful treatment of dumping syndrome with diazoxide. A 2-month-old infant with left hypoplastic heart syndrome who underwent single ventricle palliation pathway and developed feeding intolerance that required Nissen fundoplication. Postprandial hypoglycemia was detected following the procedure, with glucose level down to 12 mg/dL, and the diagnosis of dumping syndrome was established. The patient was successfully managed with diazoxide, which effectively resolved postprandial hypoglycemia without any major adverse events. The patient was eventfully weaned off the medication at the age of 5 months. This case highlights the potential role of diazoxide in the management of pediatric patients with postprandial hyperinsulinemic hypoglycemia secondary to dumping syndrome.

Learning points

• Dumping syndrome is a possible complication of gastrointestinal surgeries and should be suspected in children with abnormal glucose levels.

• Postprandial hyperglycemia should be monitored closely for significant subsequent hypoglycemia.

• Diazoxide might be considered as part of the treatment plan for dumping syndrome.

Summary

Pathogenic variants in the nuclear receptor subfamily 5 group A member 1 gene (NR5A1), which encodes steroidogenic factor 1 (SF1), result in 46,XY and 46,XX differences of sex development (DSD). In 46,XY individuals with a pathogenic variant in the NR5A1 gene a variable phenotype ranging from mild to severe is seen, including adrenal failure, testis dysgenesis, androgen synthesis defects, hypospadias and anorchia with microphallus and infertility. We report the clinical, endocrinological and genetic characteristics of a patient with 46,XY DSD with a novel likely pathogenic missense variant in the NR5A1 gene. A retrospective evaluation of the medical history, physical examination, limited endocrinological laboratory analysis and genetic analysis with DSD gene panel testing was performed. A 1.5-month-old individual was referred with ambiguous genitalia. The karyotype was 46,XY. The endocrinological analyses were within normal male reference including a normal response of cortisol within an adrenocorticotropic hormone test. A novel heterozygous missense variant c.206G>C p.(Arg69Pro) in the NR5A1 gene was detected. This variant was present in mosaic form (~20%) in his unaffected father. Because another missense variant at the same position and other missense variants involving the same highly conserved codon have been reported, we consider this NR5A1 variant in this 46,XY DSD patient as likely pathogenic in accordance with the ACMG/AMP 2015 guidelines causing ambiguous genitalia but no adrenal insufficiency. This variant was inherited from the apparently unaffected mosaic father, which might have implications for the recurrence risk in this family.

Learning points

• The importance of performing trio (patient and parents) sequencing is crucial in pointing out the origin of inheritance.

• In a 46,XY differences of sex development patient, a normal adrenal function does not rule out an NR5A1 mutation.

• With the support of a dedicated overseas institute partnership, we could solve this complex clinical case by molecular diagnosis in a resource-limited setting.

Summary

Thyrotoxic periodic paralysis (TPP) is a rare complication of hyperthyroidism triggered by precipitants that increase the activity of the sodium-potassium pump in the skeletal muscle. In our case study, a previously healthy 34-year-old male presented to the emergency department with new onset thyrotoxicosis, secondary to Graves’ disease. Given the severity of his triiodothyronine (T3) thyrotoxicosis, he was admitted and started on a high dose of beta-blocker, thioamides, and intravenous hydrocortisone. On the second day of his hospitalization, he developed acute flaccid paralysis of his lower extremities. Subsequent stroke workup was negative, and his electrolytes revealed severe hypokalemia and hyperglycemia consistent with TPP. He was treated with potassium and had a complete recovery of his paralysis and hypokalemia within hours. The patient has not had any recurrence since this singular episode in the hospital. This case highlights the scenario where the treatment of hyperthyroidism with high-dose corticosteroids to reduce the conversion of thyroxine to T3 inadvertently resulted in TPP. Clinicians should be aware of this potentially rare but serious consequence of using steroids to manage hyperthyroidism.

Learning points

• High-dose steroids used to treat hyperthyroidism in hospitalized patients may rarely precipitate thyrotoxic periodic paralysis (TPP) by inducing hypokalemia and hyperglycemia.

• TPP should be included in the differential diagnosis for acute flaccid paralysis in hospitalized patients with hyperthyroidism.

• Since TPP is associated with trans-cellular shifts in potassium instead of total body potassium depletion, conservative repletion of potassium is recommended to avoid rebound hyperkalemia.

Summary

Osilodrostat is a novel, orally administered cortisol synthesis inhibitor, approved in 2020 by the European Medicines Agency (EMA) for the treatment of Cushing’s syndrome in adults. A significant amount of the studies currently available in the literature focus on treatment in patients with Cushing’s disease. However, data collected from patients treated with osilodrostat in real-life settings still represents a small entity. For this reason, in this article, we will discuss two real-life cases of patients with Cushing’s disease treated with this drug. The first report is about a 35-year-old woman with an adrenocorticotrophic hormone (ACTH)-secreting adenoma. After non-curative trans-nasal-sphenoidal (TNS) surgery, due to a small remnant of the adenoma, medical therapy with osilodrostat achieved fast and effective biochemical and clinical response. During treatment, progressive increase of ACTH levels and an enlargement of the pituitary remnant were documented, with planned radiosurgical treatment. The second case reports a 32-year-old man diagnosed with Cushing’s disease in 2020, who, after surgery refusal, started osilodrostat at progressively up-titrated doses, according to 24 h urinary free cortisol levels, up to 5 mg twice a day. With osilodrostat, the patient reached biochemical and clinical control of disease until TNS surgery in October 2021, with complete remission. The first post-surgical biochemical assessment was equivocal in spite of a transient clinical hypoadrenalism, reverted after 2 months with the restoration of physiological hypothalamic-pituitary-adrenal axis (HPA) function.

Learning points

• Osilodrostat is a potent oral drug viable for Cushing’s disease as medical therapy when surgery is not feasible or remission cannot be reached.

• Osilodrostat proves to be a safe drug and its main adverse effect is hypoadrenalism, due to the adrenolytic action of the compound.

• Osilodrostat needs a very tailored approach in its clinical use because there is no correlation between the level of hypercortisolism pre-treatment and the dose required to reach disease control.

Summary

Diabetes mellitus type 2 (DM-2) is one of the important causes of low-grade chronic inflammation (meta inflammation) seen in almost all tissues in the body. Other possible mechanisms involved in the development of lower urinary tract symptoms (LUTS) with DM-2 are the hypertonicity of the peripheral sympathetic nerves and hyperinsulinemia effects on the autonomous nervous system activity. These further suggests that abnormalities in glucose homeostasis influence the hyperproliferation of the prostate cells resulting in benign prostatic hyperplasia (BPH). Similarly, hepatic steatosis, a form of non-alcoholic fatty liver disease (NAFLD) prevalence among patients with DM-2, is as high as 75%. NAFLD has no symptoms in most diabetic patients. In this study, we present a case of a 64-year-old Black male who had worsening urinary urgency and hesitancy for 4 months, with increasing abdominal girth. Patient was found to have symptoms, diagnostic studies, and physical exam findings indicative of BPH and fatty liver disease. He was treated with hepato-protective medications, tighter control of his blood glucose levels, and blood pressure meds for 13 months. Upon follow-up, most of his symptoms were resolved. Timeline of BPH resolution and decrease in liver size following treatment suggest that DM-2 has a strong correlation with the development of BPH and fatty liver disease in most patients living with diabetes.

Learning points

• Men with type 2 diabetes mellitus (DM-2) tend to have significantly lower serum PSA level, lower testosterone levels, and larger prostate volume compared to non-diabetic male patients.

• Patients with DM-2 have higher prevalence of hepatic steatosis, liver cirrhosis, and end-stage liver failure.

• The role of metformin in reducing hepatic steatosis as stated by several studies is yet to be validated as our patient has been on metformin for 22 years for the management of DM-2 with fatty liver disease.