Whole-genome sequencing revealed armadillo repeat containing 5 (ARMC5) mutation in a Chinese family with ACTH-independent macronodular adrenal hyperplasia.

Primary macronodular adrenal hyperplasia (PMAH), also known in the past as bilateral macronodular adrenalhyperplasia or adrenocorticotropin (ACTH)-independent macronodular adrenal hyperplasia, is a rare type of Cushing's syndrome (CS) and is associated with bilateralenlargement of the adrenal glands. It accounts for <1% of all endogenous cases of CS. In order toidentify the pathogenic mutations in the causative gene of (AIMAH pedigrees, Whole-genome sequencing of three patients in family I was used to retrieve candidate causative genes. Meanwhile, the causative gene was identified by Sanger sequencing from the two pedigrees. Sequencing of ARMC5 exons of three patients was carried out to identify somatic mutations. Moreover, haploid clone of one tumor DNA sample was conducted. ARMC5 was the causative gene of two pedigrees confirmed by whole-genome sequencing (WGA) and Sanger sequencing. The variant sites of the two families were c.C943T (p.R315W) and c.C1960T (p.R654X), respectively. Autosomal dominant inheritance of AIMAH was confirmed by genotypes of one family member. Several somatic mutations were discovered in tumor DNA samples. In addition, haploid clone of tumor DNA was confirmed by germline mutation and somaticmutation, which suggested the pathogenic mechanism of "two-hit-model." ARMC5 was the causative gene of AIMAH pedigrees. This AIMAH in this study presented autosomal dominant inheritance, fitting to Mendelian inheritance law. However, the pathogenic mode of this disease showed as compound heterozygote.

Cardiovascular disease outcomes in metabolically healthy obesity in communities of Beijing cohort study.

OBJECTIVE: The objective of this study was to investigate the association between metabolically healthy obese (MHO) phenotype and the risk of cardiovascular disease (CVD). METHODS: A total of 9393 subjects aged ≥40 years were enrolled in the cohort study (2011-2015). The participants were stratified by body mass index category and metabolic risk at baseline, and incidence of CVD was ascertained at follow-up. RESULTS: The MHO accounted for 6.7%. Compared with the metabolically healthy normal weight (MHNW) group, MHO subjects demonstrated increased risk of CVD events (HR = 1.91; 95% CI, 1.13-3.24). In people with obesity, there was no significant difference on increasing risk of incidence of CVD in the metabolically unhealthy individuals compared with metabolically healthy individuals (HR = 1.19; 95% CI, 0.74-1.91). Female (OR = 1.97; 95% CI, 1.06-3.64), smoking (OR = 2.09; 95% CI, 1.06-4.10), a larger waist circumference (OR = 1.07; 95% CI, 1.03-1.10) and higher LDL cholesterol levels (OR = 1.55; 95% CI, 1.20-2.00) were independent risk factors of the development of the MHO to the metabolically unhealthy obese (MUO) phenotype. CONCLUSIONS: The risk of CVD events of MHO phenotypes is similar to MUO phenotypes; both are higher than the MHNW phenotypes.

Multi-genic pattern found in rare type of hypopituitarism: a whole-exome sequencing study of Han Chinese with pituitary stalk interruption syndrome.

Pituitary stalk interruption syndrome (PSIS) is a rare type of hypopituitarism manifesting various degrees of pituitary hormone deficiency. Although mutations have been identified in some familial cases, the underpinning mechanisms of sporadic patients with PSIS who are in a vast majority remain elusive, necessitating a comprehensive study using systemic approaches. We postulate that other genetic mechanisms may be responsible for the sporadic PSIS. To test this hypothesis, we conducted a study in 24 patients with PSIS of Han Chinese with no family history using whole-exome sequencing (WES) and bioinformatic analysis. We identified a group of heterozygous mutations in 92% (22 of 24) of the patients, and these genes are mostly associated with Notch, Shh, Wnt signalling pathways. Importantly, 83% (20 of 24) of the patients had more than one mutation in those pathways suggesting synergy of compound mutations underpin the pathogenesis of sporadic PSIS.

Type B insulin resistance syndrome with Scleroderma successfully treated with multiple immune suppressants after eradication of Helicobacter pylori infection: a case report.

BACKGROUND: Type B insulin resistance is a rare autoimmune disease characterized by the presence of autoantibodies against the insulin receptor. Helicobacter pylori (H pylori) infection may play a causative role in the autoimmune diseases. CASE PRESENTATION: Here, we present a rare case of a 48-year old female patient, who had type B insulin resistance with systemic scleroderma and was successfully treated with multiple immune suppressants after eradication of Helicobacter pylori infection. CONCLUSION: The present case suggests H pylori infection-related pathological mechanism may contribute to type B insulin resistance syndrome and autoimmune disorders. Treatment toward H pylori may be helpful to relieve syndrome of type B insulin resistance for H pylori positive patients.

Malignant insulinoma: Report of 6 patients and literature review.

OBJECTIVE: Patients with malignant insulinoma always present with symptoms of severe hypoglycemia and have poor life expectancy. In addition, inoperable metastatic malignant insulinomas are very difficult to manage. The aim of this report is to present our successful experiences in diagnosis and treatment of this disease in 6 patients. PATIENTS/METHODS: Six patients (male 2, female 4) with malignant insulinomas were admitted into our hospital. Their clinical histories, including clinical presentations, endocrine evaluations, radiological images, pathological examination and treatments, were reviewed. RESULTS: The diagnosis of malignant insulinoma combined with liver metastases was confirmed in all patients by endocrine evaluation and radiological images. Patients 1-3 underwent surgical management. The primary and metastasized tumors were completely resected. After successful surgery, no hypoglycemia recurred. Patients 4-6 did not undergo surgery because of systemic disease and poor health. Instead, they were administrated with diazoxide 50 mg Three Times a Day (TID), with final doses up to 200-300 mg TID. These 3 patients had good responses to diazoxide administration. After treatment, the frequency and severity of hypoglycemia were improved significantly. All 6 patients had better life quality than previously expected. CONCLUSION: Combination of surgical and medical approaches can improve life quality and prolong survival of patients with malignant insulinomas.

Correlation between Pituitary Stalk Interruption Syndrome and Prokineticin Receptor 2 and Prokineticin 2 Mutations.

OBJECTIVE: To analyze the correlation between pituitary stalk interruption syndrome (PSIS) and prokineticin receptor 2 (PROKR2) and prokineticin 2 (RROK2) mutations. METHODS: PROKR2 and RROK2 genotypes were identified by multiplex polymerase chain reaction analysis with exon-flanking primers and by automated sequencing techniques with peripheral blood DNA samples from 59 patients with PSIS. RESULTS: Of these 59 PSIS patients, 6 showed intragenic deletions at the PROKR2 locus. Of them, 5 patients exhibited intragenic subsititution of exon 2 (c.991G>A), and the remaining one patient exhibited intragenic subsititution of exon 2 (c.1057C>T). No PROK2 mutation was found in these PSIS patients. CONCLUSION: PROKR2 may be the susceptibility gene of PSIS.

Clinical Features of Pituitary Stalk Interruption Syndrome in 114 Cases.

Objective To analyze the clinical characteristics of pituitary stalk interruption syndrome(PSIS). Methods The clinical data including clinical manifestations,laboratory tests,and imaging findings of 114 PSIS patients in our hospital were retrospectively analyzed. Results Of these 114 PSIS patients,102 cases (89.4%) were male. The average age was 21.1?6.1 years. A history of breech delivery was documented in 91 cases (91.9%). Short stature was found in 89 cases (71.8%) and bone age delayed (6.1?5.1) years. Secondary sex characteristics were poor or undeveloped in most patients. The prevalence of deficiencies in growth hormone,gonadotropins,corticotropin,and thyrotropin were 100.0%,94.0%,84.2%,and 74.6%,respectively. Hyperprolactinemia was found in 28.1% of patients. Three or more pituitary hormone abnormalities were found in 105 cases(92.1%). Compared with the 5 cases with history of cephalic delivery,no difference were found in the aspects of height(t=0.297,P=0.634),penile length(t=1.205,P=0.882),testicular volume (U=99.000,P=0.348),growth hormone peak (U=89.000,P=0.186),adrenocorticotropic hormone peak(U=131.000,P=0.967),luteinizing hormone peak(U=98.500,P=0.582),thyroid-stimulating hormone (U=82.000,P=0.162),and the height of anterior pituitary (t=1.676,P=0.107) in the 53 cases with history of breech delivery. Conclusions The clinical manifestations,symptoms,hormone deficiencies were severe in our series. The condition severities were not remarkably different in patients with different delivery ways.

Acquired generalized lipodystrophy in a young lean Chinese girl. Case Report.

Lipodystrophies is a really rare group of diseases characterized by altered body fat amount and/or repartition and serious insulin resistance.We reported a lean Chinese girl with acquired generalized lipodystrophy, who had a long history of poorly controlled diabetes mellitus (DM) despite with extremely high dose insulin (6 u/kg/d) therapy, combined with severe hypertriglyceridemia and acanthosis nigricans. The differential diagnosis of Lipodystrophies should be considered in lean patients presenting with early onset DM, combined with serious insulin resistance.

Pituitary stalk interruption syndrome in 58 Chinese patients: clinical features and genetic analysis.

OBJECTIVES: Pituitary stalk interruption syndrome (PSIS) is rare and its clinical features and pathogenesis are poorly understood. This study characterized the clinical and genetic features of PSIS in Chinese patients. DESIGN AND PATIENTS: Clinical data of 58 patients with PSIS and 46 patients with GH deficiency but a normal pituitary stalk (NPS) were retrospectively analysed. HESX1, LHX4, OTX2 and SOX3 polymorphisms were screened in 33 PSIS patients, and GH1 and GHRHR in 4 NPS patients. RESULTS: Deficiency of GH was 100% in both PSIS and NPS groups. Other deficiency rates for PSIS and NPS groups were as follows: ACTH, 77·6% and 23·9%; TSH, 43·1% and 10·9%; LH/FSH, 94·2% and 47·4%; and combined pituitary hormone, 93·1% and 41·3% respectively. In PSIS and NPS patients, the percentages of anterior pituitary hypoplasia were 98·3% and 54·3%, pituitary stalk abnormality were 100% and 0%, and ectopic neurohypophysis were 91·4% and 0%. A novel heterozygous sequence variant (c.142A>T, p.T48S) was found in HESX1 in one PSIS patient, 3 polymorphisms (c.63T>C, p.G21G; c.450C>T, p.N150N; and c.983A>G, p.N328S) in LHX4 in 7, 1 and 31 PSIS patients, respectively, and a hemizygous polymorphism (c.157G>C, p.V53L) in SOX3 in one PSIS patient. No OTX2 abnormality was detected in PSIS patients, and no GH1 or GHRHR polymorphisms in NPS patients. CONCLUSIONS: Compared with NPS, PSIS patients had more severe anterior pituitary hormone deficiency, lower anterior pituitary hormone secretion and higher probability of abnormal pituitary morphology. HESX1, LHX4 and SOX3 polymorphisms may be associated with PSIS.

Female sex hormones are associated with the reduction of serum sodium and hypertension complications in patients with aldosterone-producing adenoma.

This study was conducted to evaluate gender-related differences in clinical characteristics and vascular complications in patients with aldosterone-producing adenomas (APA). Clinical characteristics, biochemical markers and incidence of vascular complications were compared by gender in 187 consecutive patients with APA confirmed by pathological diagnosis. Patients were separated into two groups based on ages either older or younger than 49 years, the average age of menopause among Chinese women (<49 y and ≥49 y). Males had significantly higher BMI than females in the age group of <49 years (p = 0.017). In the <49 years group, males had significantly higher serum sodium levels (p = 0.003). However, no such gender differences in clinical characteristics were observed in patients ≥49 years. A higher proportion of vascular complications was observed in males as compared to females aged <49 years but the difference was not statistically significant (51.4% vs. 34.8%, p = 0.105). The only gender difference observed in vascular complications between patients aged ≥49 years was that a significantly greater proportion of males had cerebrovascular complication compared to females (p = 0.006). Our data suggest that female sex hormones are implicated in reducing serum sodium concentration and vascular complications in female APA patients.

Effects of a multivitamin/multimineral supplement on young males with physical overtraining: a placebo-controlled, randomized, double-blinded cross-over trial.

OBJECTIVE: To investigate the effects of vitamin-mineral supplement on young males with physical overtraining. METHODS: Two hundred and forty male Chinese field artillery personnel who undertook large scale and endurance military training and were on ordinary Chinese diet were randomized to receive a multivitamin/multimineral supplement or a placebo for 1 week. After a 1-week wash-out period, a cross-over with 1 week course of a placebo or multivitamin/multimineral supplement was conducted. Blood and urine samples were analyzed for adrenal, gonadal and thyroid hormones. In addition, cellular immune parameters (CD3+, CD3+CD4+, CD3+CD8+, CD4/CD8, CD3-CD56+, CD3-CD19+) were examined and psychological tests were performed before and after the training program and nutrition intervention. RESULTS: After a large scale and endurance military training, the participants showed significantly increased thyroid function, decreased adrenal cortex, testosterone and immunological function, and significantly increased somatization, anger and tension. Compared to placebo, multivitamin/ multimineral intervention showed significant effects on functional recovery of the pituitary - adrenal axis, pituitary-gonadal axis, pituitary- thyroid axis and immune system as well as psychological parameters. CONCLUSION: High-intensity military operations have significant impacts on the psychology, physical ability and neuroendocrine-immune system in young males. Appropriate supplementation of multivitamin/multimineral can facilitate the recovery of the psychology, physical ability and neuroendocrine-immune system in young males who take ordinary Chinese diet.

[The clinical characteristics of multi-detector computed tomography of congenital adrenal hyperplasia].

OBJECTIVE: To explore the imaging features of congenital adrenal cortex hyperplasia (CAH). METHODS: A total of 45 patients clinically confirmed as CAH were retrospectively analyzed to investigate the imaging features and strengthening way of the multi-detector-row Computed tomography. RESULTS: The imaging features of all the cases presented as following: 25 with bilateral adrenal hyperplasia, 6 with unilateral adrenal hyperplasia, 6 with adrenal nodular hyperplasia, 2 with adrenal hyperplasia and unilateral solid cystic lesion, 2 with adrenal hyperplasia and double side real cystic lesion, 1 with adrenal hyperplasia and unilateral cystic changes and 3 with normal adrenal. The unilateral or bilateral hyperplasia adrenal could be homogeneously enhanced, while the enhanced performance of other cases was inequitable. CONCLUSIONS: The adrenal imaging features of CAH by multi-detector-row CT are variable, with the bilateral adrenal hyperplasia as the main form, which could be restored to normal morphology after hormone replacement therapy.No regression of the tumor size is observed in cases with adrenal mass. CT scanning combined with clinical manifestation and biochemical examination could facilitate the diagnosis of CAH.

Albuminuria independently predicts cardiovascular and all-cause mortality in a middle-aged and elderly Chinese population.

AIM: To investigate the relationship between albuminuria and mortality in a middle-aged-to-elderly Chinese population. METHODS: A total of 2,344 individuals aged over 40 in the same district were interviewed and followed up for 4 years. Information on survival or cause of death was recorded. A total of 2,181 participants with detailed information were finally recruited. Baseline overnight urine samples were obtained to measure urinary albumin and creatinine. The urinary albumin excretion rate was expressed as albumin-to-creatinine ratio (ACR). Participants were divided into three groups, according to their ACR: normoalbuminuria (ACR < 30 mg/g), microalbuminuria (≥ 30 - < 300 mg/g ACR) and macroalbuminuria (ACR ≥ 300 mg/g). The Cox proportional hazard model was used to analyze the relationships between albuminuria and cardiovascular and all-cause mortalities. RESULTS: Seventy-seven deaths with known causes were registered. The prevalences of microalbuminuria and macroalbuminuria at baseline were 8.3% and 1.6%, respectively. Cardiovascular mortalities in the normoalbuminuria, microalbuminuria and macroalbuminuria groups were 2.4, 11.0, and 36.8/1,000 person years (pyrs) respectively, and all-cause mortalities were 6.9, 20.6, and 58.8/1,000 pyrs. After adjusting for confounding factors, the relative risks (RR) of cardiovascular mortality were 2.72 (95% CI, 1.06-4.20) in the microalbuminuria group, and 4.87 (95% CI, 2.46-9.45) in the macroalbuminuria group. Adjusted RRs for all-cause mortality were 2.01 (95% CI, 0.96-4.77) and 3.76 (95% CI, 1.52-7.15) in the two groups, respectively. CONCLUSION: Albuminuria is a useful predictor of cardiovascular mortality and all-cause mortality in the general population.

Clinical and genetic analysis of three Chinese patients with steroid 5α-reductase type 2 deficiency.

Steroid 5α-reductase type 2 deficiency (5α-RD2) is a rare autosomal recessive inherited disorder caused by mutations in the SRD5A2 gene. Its clinical features and pathogenesis in Chinese patients are poorly understood. This study aimed to characterize the clinical features and genetically analyze the SRD5A2 gene in three Chinese 5α-RD2 patients. The patients were characterized by ambiguous genitalia and spontaneous virilization without breast development at puberty. Elevated post-human chorionic gonadotropin stimulation T/DHT ratios were useful indicators of 5α-RD2 (with ratios of 20.4, 20.1, and 26.6 in the three patients, respectively). Two compound heterozygous mutations in the SRD5A2 gene were identified: p.G203S/p.R246Q in patients 1 and 2 and p.G203S/c.655delT in patient 3. The father and the mother of patients 1 and\xa02 were carriers of p.R246Q and p.G203S, respectively. p.G203S appears to be common in Chinese 5α-RD2 patients. Early genetic analysis should be performed in suspected patients to improve prognosis.

Laparoscope resection of ectopic corticosteroid-secreting adrenal adenoma.

Tumors originating from ectopic adrenal tissue are relatively rare. In this article, we describe a case with Cushing's syndrome caused by an ectopic adrenal adenoma. A 38 year-old male patient presenting with cushingoid appearance for 2 years was diagnosed to have ACTH-independent Cushing's syndrome based on endocrinological evaluation. Mutiple radiological examinations detected bilateral adrenal atrophy. When the images were investigated in a more expanded scope, a 3.0×3.5×5.3 cm mass was detected in the anterior of left renal hilum and left renal vein. The mass was successfully resected with intraoperative endoscopy and pathological evaluation revealed an ectopic adrenal tumor. It is suggested that when the endocrinlogically confirmed adrenal neoplasm could not be well and definitely localized, the possibility of ectopic adrenal should be presumed and further radiography examinations should extend to the field where ectopic adrenal usually presents.

Parathyroid carcinoma: Report of 10 patients and literature review.

OBJECTIVE: Parathyroid carcinoma (PC) is a rare disease with high rates of misdiagnosis and recurrence. This report summarized the clinical and pathological characteristics of 10 patients with PC at our hospital, to improve the early recognition and prognosis of PC. METHODS: The clinical manifestations, imaging findings, pathological features, treatments, and prognostic data of 10 patients diagnosed with PC at the First Medical Center, Chinese PLA General Hospital from 2003 to 2021 were analyzed. RESULTS: There were 7 male and 3 female patients with PC whose average age was 41.4 ± 9.4 years. All patients had bone involvement (bone pain and/or osteoporosis), meanwhile 6 patients had kidney stones and 7 patients had palpable neck masses. Five patients presented with tumor metastasis, invading lymph nodes, lung, liver, or bone. Laboratory examinations revealed elevated serum total calcium (4.15 ± 0.81 mmol/L), parathyroid hormone (PTH, 1236.1 ± 519.9 pg/mL) and alkaline phosphatase (405.8 ± 219.0 IU/L) levels. Especially, hypercalcemic crisis occurred in 9 patients. The diagnosis of PC depended on histopathological features of the parathyroid tumor, including capsular and/or vascular invasion. All patients underwent at least en bloc resection. In the follow-up, six patients with relatively high preoperative PTH levels (1519.5 ± 436.8 pg/mL) relapsed postoperatively. Two patients with the Ki-67 index ≥ 10% in parathyroid tumor tissue and distant metastasis died within 2 years after the operation. CONCLUSION: Severe bone pain, kidney stones, hypercalcemic crisis, and markedly elevated PTH usually indicate PC. A markedly elevated PTH level, tumor metastasis, and the Ki-67 index ≥ 10% may be indicators of poor prognosis.

Clinical data analysis of 22 cases with hypoparathyroidism misdiagnosed as epilepsy.

OBJECTIVE: Patients with hypoparathyroidism always present with recurrent tetany caused by hypocalcemia. These patients are usually misdiagnosed with epilepsy and incorrectly treated with anti-epileptic drugs. This research analyzed clinical data about 22 patients with hypoparathyroidism misdiagnosed as epilepsy and summarized the clinical experience for reducing misdiagnosis and incorrect therapy about hypoparathyroidism. METHOD: Totally 160 patients with hypoparathyroidism, administrated to the First Medical Center of Chinese PLA General Hospital from January 1st, 2008, to July 1st, 2021, were enrolled in this report. Clinical data about 22 patients initially misdiagnosed with epilepsy were analyzed. RESULTS: Of the 160 cases with hypoparathyroidism, 22 patients (12 males and 10 females) were misdiagnosed with epilepsy in local hospitals. The misdiagnosis rate was 13.75% and the median duration of misdiagnosis was 8.0 (2.0, 14.8) years. The clinical manifestations of the 22 patients misdiagnosed as epilepsy included tetany 81.8% (18/22), disturbance of consciousness 27.3% (6/22), limb numbness 13.6% (3/22), limb weakness 27.3% (6/22), mental and behavioral abnormality 9.1% (2/22), and memory impairment 13.6% (3/22), etc. Electroencephalogram (EEG) was performed in 9 cases, which presented as slow wave and spike-slow complex wave in 3 cases, slowing down of Î¸ and δ band background in 2 cases and normal EEG in 4 cases. Out of the 15 cases that underwent head computed tomography (CT) scan, in which 13 cases had intracranial calcification. Anti-epileptic drugs were used to treat 22 patients, of which 17 patients were treated with two kinds of drugs. With calcium and calcitriol supplement in all these 22 patients, the anti-epileptic drugs were gradually reduced and withdrawn in 17 cases. In the other 5 cases with secondary epilepsy, the type of anti-epileptic drugs was reduced to one and the clinical condition improved obviously. CONCLUSION: The clinical manifestations of hypoparathyroidism are complex and usually be misdiagnosed as primary epilepsy. Detection of serum calcium, phosphorus and parathyroid hormone is very important to avoid misdiagnosis and incorrect therapy about hypoparathyroidism.

A young boy with diffuse hyperpigmentation and delayed puberty.

An 18-year-old male patient had presented with diffuse hyperpigmentation after birth and with adrenal insufficiency syndrome since childhood. After puberty, no secondary sexual signs developed. Laboratory examination showed an extremely high concentration of serum triglycerides (9.14 mmol/L) and plasma adrenocorticotropic hormone (>275 pmol/L), however, a low concentration of plasma free cortisone (<25.1-67.6 nmol/L). Abdomen computed tomography detected atrophy of both adrenals glands.

Recurrent autoimmune hypophysitis successfully treated with glucocorticoids plus azathioprine: a report of three cases.

Recurrent autoimmune hypophysitis is a rare autoimmune endocrine disease involving lymphocytic infiltration and chronic pituitary inflammation. It is even more rare than primary hypophysitis. The objective of the study was to evaluate the efficacy of glucocorticoid treatment combined with azathioprine for treating three cases of recurrent autoimmune lymphocytic hypophysitis encountered within a two-year period. The clinical features and follow-up data of these cases were analyzed, including results of treatment with glucocorticoids combined with azathioprine. All three patients were female and presented with the following clinical characteristics: case 1 was a 22-year-old with headache and diplopia; case 2 was a 70-year-old with dry mouth, polydipsia, and polyuria; case 3, a 32-year-old, with polydipsia, polyuria and menstrual disorders with headache and dizziness. Regarding recurrence, case 1 recurred 4 months after surgery and again 14 months after discontinuing prednisone; case 2 relapsed 16 months after receiving high-dose methylprednisolone pulse therapy; and case 3 recurred during the period of prednisone dose reduction. The patients were treated with glucocorticoids plus azathioprine, and positive responses were seen in all three cases. Symptoms were relieved, and MRI revealed significant reduction of lesions during follow-up. Pituitary function resumed in cases 1 and 3; permanent hypopituitarism was present in case 2. At last follow-up, MRI showed no further recurrence of disease in any patient. Treatment and responses of these patients with autoimmune hypophysitis suggest that glucocorticoid therapy combined with azothioprine is effective treatment for recurrent autoimmune hypophysitis. Endocrine and radiologic studies are an essential part of follow-up.

Medullar thyroid carcinoma in mediastinum initially presenting as Ectopic ACTH syndrome. A case report.

A rare case with ectopic adrenocorticotrophic hormone syndrome (EAS) caused by medullar thyroid carcinoma (MTC) in mediastinum was reported. This 49 year-old male patient initially presented with serious and intractable hypokalemia. Endocrine evaluations showed increased levels of adrenocorticotrophic hormone (ACTH) and urinary free cortisol, which could not be suppressed more than 50% by high-dose dexamethasone suppression test. Computed tomography (CT) scan detected a 5×5×5 cm mass at the bottom of thyroid in anterior mediastinum. The patient underwent total thyroidectomy with central compartment and ipsilateral modified radical neck dissection. Pathological examination showed an infiltrating thyroid medullary carcinoma with abundant amyloid deposition, meanwhile immunohistochemical positive for ACTH. After surgery, serum levels of kalium, as well as cortisol and ACTH returned to normal range. During follow-up, the patient's clinical manifestation of Cushing syndrome relieved.