down 's syndrome ( ds ) is one of the common chromosomal disorders and the most common cause of mental retardation . it is well - known that patients with ds have an increased prevalence of autoimmune disorders affecting both endocrine and non - endocrine organs . although cases of ds associated with diabetes mellitus ( dm ) have been reported in the past , invariably all cases were associated with type 1 dm . we present two cases of type 2 dm with ds and believe that this is the first report of type dm with ds . a 28-year - old male patient with a body mass index ( bmi ) of 25.1 kg / m and positive family history of dm reported to the out - patient clinic of the department of endocrinology , medwin hospital with the clinical features of polyuria and polydipsia for last 1 year . physical examination revealed typical mongolian facies and other features of ds such as short stature ( 145 cm ) , brachycephaly , short neck and pot belly , small mouth with protruding tongue , wide occipital region and characteristic small eyes of ds . laboratory data revealed diabetes with fasting plasma glucose of 256 mg / dl , postprandial plasma glucose of 375 mg / dl and glycated hemoglobin ( hba1c ) level of 9.9% . c - peptide assay showed fairly well - preserved pancreatic  cell function : fasting values of 1.3 pmol and stimulated values of 2.4 pmol / ml ( normal values in non - diabetic subjects , fasting > 1.5 pmol / ml and stimulated > 4.0 pmol / ml ) . glutamic acid decarboxylase ( gad ) antibody testing ( 3.2 iu / ml ) was negative . other investigations ( hemogram , renal and liver function parameters , serum electrolytes and lipid profile ) were within the normal limits . he was initiated on basal glargine insulin at a dose of 15 units subcutaneously at night along with oral hypoglycemic agent ( glimepiride 2 mg / metformin 1000 mg ) once daily and l - thyroxine 100 g daily . later , the doses of insulin were reduced and subsequently withdrawn completely and he is maintained well on oral hypoglycemic agents alone . a 26-year - old female patient with a bmi of 33.4 kg / m with strong family history of dm were admitted in the in - patient department of endocrinology , medwin hospital for proper control of hyperglycemia . physical examination revealed features of ds ( short stature , obesity , brachycephaly , gynecomastia , protruding tongue , simian crease , pot belly , short neck and acanthosis nigricans , wide occipital region with characteristic small eyes ) . the laboratory evaluation revealed fasting and postprandial sugar levels as 175 mg / dl and 240 mg / dl , respectively hba1c of 8.9% . his fasting and stimulated c - peptide levels were 1.4 pmol / ml and 2.5 pmol / ml with negative gad - antibody test ( 4.1 iu / ml ) . a 28-year - old male patient with a body mass index ( bmi ) of 25.1 kg / m and positive family history of dm reported to the out - patient clinic of the department of endocrinology , medwin hospital with the clinical features of polyuria and polydipsia for last 1 year . physical examination revealed typical mongolian facies and other features of ds such as short stature ( 145 cm ) , brachycephaly , short neck and pot belly , small mouth with protruding tongue , wide occipital region and characteristic small eyes of ds . laboratory data revealed diabetes with fasting plasma glucose of 256 mg / dl , postprandial plasma glucose of 375 mg / dl and glycated hemoglobin ( hba1c ) level of 9.9% . c - peptide assay showed fairly well - preserved pancreatic  cell function : fasting values of 1.3 pmol and stimulated values of 2.4 pmol / ml ( normal values in non - diabetic subjects , fasting > 1.5 pmol / ml and stimulated > 4.0 pmol / ml ) . glutamic acid decarboxylase ( gad ) antibody testing ( 3.2 iu / ml ) was negative . other investigations ( hemogram , renal and liver function parameters , serum electrolytes and lipid profile ) were within the normal limits . he was initiated on basal glargine insulin at a dose of 15 units subcutaneously at night along with oral hypoglycemic agent ( glimepiride 2 mg / metformin 1000 mg ) once daily and l - thyroxine 100 g daily . later , the doses of insulin were reduced and subsequently withdrawn completely and he is maintained well on oral hypoglycemic agents alone . a 26-year - old female patient with a bmi of 33.4 kg / m with strong family history of dm were admitted in the in - patient department of endocrinology , medwin hospital for proper control of hyperglycemia . physical examination revealed features of ds ( short stature , obesity , brachycephaly , gynecomastia , protruding tongue , simian crease , pot belly , short neck and acanthosis nigricans , wide occipital region with characteristic small eyes ) . the laboratory evaluation revealed fasting and postprandial sugar levels as 175 mg / dl and 240 mg / dl , respectively hba1c of 8.9% . his fasting and stimulated c - peptide levels were 1.4 pmol / ml and 2.5 pmol / ml with negative gad - antibody test ( 4.1 iu / ml ) . a 28-year - old male patient with a body mass index ( bmi ) of 25.1 kg / m and positive family history of dm reported to the out - patient clinic of the department of endocrinology , medwin hospital with the clinical features of polyuria and polydipsia for last 1 year . physical examination revealed typical mongolian facies and other features of ds such as short stature ( 145 cm ) , brachycephaly , short neck and pot belly , small mouth with protruding tongue , wide occipital region and characteristic small eyes of ds . laboratory data revealed diabetes with fasting plasma glucose of 256 mg / dl , postprandial plasma glucose of 375 mg / dl and glycated hemoglobin ( hba1c ) level of 9.9% . c - peptide assay showed fairly well - preserved pancreatic  cell function : fasting values of 1.3 pmol and stimulated values of 2.4 pmol / ml ( normal values in non - diabetic subjects , fasting > 1.5 pmol / ml and stimulated > 4.0 pmol / ml ) . glutamic acid decarboxylase ( gad ) antibody testing ( 3.2 iu / ml ) was negative . other investigations ( hemogram , renal and liver function parameters , serum electrolytes and lipid profile ) were within the normal limits . he was initiated on basal glargine insulin at a dose of 15 units subcutaneously at night along with oral hypoglycemic agent ( glimepiride 2 mg / metformin 1000 mg ) once daily and l - thyroxine 100 g daily . later , the doses of insulin were reduced and subsequently withdrawn completely and he is maintained well on oral hypoglycemic agents alone . a 26-year - old female patient with a bmi of 33.4 kg / m with strong family history of dm were admitted in the in - patient department of endocrinology , medwin hospital for proper control of hyperglycemia . physical examination revealed features of ds ( short stature , obesity , brachycephaly , gynecomastia , protruding tongue , simian crease , pot belly , short neck and acanthosis nigricans , wide occipital region with characteristic small eyes ) . the laboratory evaluation revealed fasting and postprandial sugar levels as 175 mg / dl and 240 mg / dl , respectively hba1c of 8.9% . his fasting and stimulated c - peptide levels were 1.4 pmol / ml and 2.5 pmol / ml with negative gad - antibody test ( 4.1 iu / ml ) . previous studies had suggested that type 1 dm is more prevalent in people with ds than in the general population and vice versa . to the best of our knowledge , impaired  cell function and insulin sensitivity are the main factors in the pathogenesis of type 2 dm . cell function was fairly preserved in these two patients ( as indicated by c - peptide levels in the blood ) with negative antibody testing for gad - ab . this indicated toward the fact that impaired insulin sensitivity might have contributed to a greater extent in the development of type 2 dm in these two patients . a variety of genetic syndromes have been described in which dm occurs with increased frequency . the etiology of the disturbance in glucose homeostasis in these diverse and unrelated syndromes remain undefined . since rare forms a disease often provide insight into the possible mechanisms of the disease and since each candidate gene contributes a small amount of genetic risk to the disease , individuals with ds and type 2 dm may therefore provide the clinical insights into possible mechanisms underlying susceptibility to diabetes . further investigations are warranted to prove whether the presence of type diabetes in patients with ds was a chance association or whether there is a genetic basis for this association . however , these two cases point to the fact that one should screen patients with ds for type 2 diabetes .
down 's syndrome ( ds ) is known to be associated with autoimmune disease including type 1 diabetes . to the best of our knowledge , 
 there are no reports of ds with type 2 diabetes mellitus in the literature . 
 we hereby report two cases of ds with type 2 diabetes .