Endocrinology Lecture Notes PDF

Endocrinology Dr. Mohamed Roshdi ,MD Assistant Prof. Internal medicine  Learning Objectives Knowledge Relate pathophysiological basics and etiology of diabetes mellitus Describe epidemiology, manifestations, complications and management of diabetes mellitus Skills Interpret clinical...

Endocrinology Dr. Mohamed Roshdi ,MD Assistant Prof. Internal medicine  Learning Objectives Knowledge Relate pathophysiological basics and etiology of diabetes mellitus Describe epidemiology, manifestations, complications and management of diabetes mellitus Skills Interpret clinical manifestations and investigations of diabetes mellitus to formulate reasonable diagnosis. Apply evidence-based management plan for diabetes mellitus Distinguish patients in emergency situations to formulate a comprehensive management plan; ensuring keeping patients in normal homeostasis Diabetes Mellitus Definition: Disturbance of carbohydrate metabolism due to insulin deficiency, resistance or both leading to hyperglycaemia ± glucosuria with 2ry disturbance of protein & fat metabolism. Incidence: It is the most common endocrine disease & its frequency is about 1 - 2 %. Aetiology: A. Primary diabetes (> 95 %) a) Type I : Insulin- dependent diabetes mellitus (IDDM) "previously termed Juvenil - onset diabetes ".  There is insulin deficiency due to damage of B - cells. b) Type 2 Non insulin - dependent DM. ( NIDDM) ‘previously termed maturity onset DM’  There may be: o Insulin resistance o Abnormal structure of insulin combined with relatively reduced insulin secretion which in some cases becomes absolute There are numerous theories as to the exact cause and mechanism in type 2 diabetes:  Central obesity (fat concentrated around the waist in relation to abdominal organs, but not subcutaneous fat) is known to predispose individuals to insulin resistance. Abdominal fat is especially active hormonally… Secreting a group of hormones called adipokines that may possibly impair glucose tolerance. Obesity is found in approximately 55% of patients diagnosed with type 2 diabetes.  family history: (type 2 is much more common in those with close relatives who have had it).. NORMAL ABNORMAL  Item Type 1 (IDDM) Type 2 (NIDDM) Incidence 10 % 90 % Age of onset < 30 year ( usually 12- > 40 years sex 14 yrs) more in ♂ more in ♀ Body weight Usually underweight Usually overweight Severity Severe Mild or moderate Stability Unstable (brittle Stable diabetes) Insulin Necessary Usually not required Oral hypoglycemic Ineffective ( at least at the onset) Effective  SIGNS AND SYMPTOMS Presentations of diabetes: l. Asymptomatic & accidentally discovered. 2. Classic symptoms: Polyuria. Polydipsia. Polyphagia ( + weight loss especially in IDDM ). Pruritis (especially of the valva and anal region ). Parathesia & premature loosening of teeth. Repeated infection (e.g. boils). 3. Complications. 4. Diabetic coma. Investigations: 1.Plasma glucose (fasting & 2 hours post-prandial & oral glucose tolerance test, OGTT): Normal level: o Fasting ( < 100 mg % ). o 2 hours post-prandial on OGTT( < 140 mg % ). Impaired glucose tolerance ( I GT ): o Fasting ( ≥100 & < l26 mg %) IFG o 2 hrs post-prandial onOGTT ( ≥ 140 & < 200 mg % ).  Overt diabetes: o Fasting ( ≥ 126 mg %), o 2 hours post-prandial on OGTT ( ≥200 mg % ). o Symptoms of diabetes plus causal plasma glucose conc. ≥ 200 mg/dl. N.B: Recently HAIC also added for diagnosis of DM 2.Urine analysis : For glucose : using strips & less commonly solutions e.g. Benedict. For ketone bodies : using strips & Rothera's Na nitroprusside test. 3.Monitoring of treatment : Home blood glucose monitoring (HBGM) or urine testing for glucose. Glycosylated haemoglobin ( HA1c) : o It is formed by linkage of glucose to B-chains of Hb A. o Its measurement is used to estimate diabetic control for the preceding several weeks (8 - 12 weeks). o Normal level 6 % of the total Hb. Management There is an exceptionally important role for patient education, dietetic support, sensible exercise, self monitoring of blood glucose, with the goal of keeping blood glucose levels within acceptable bounds …  The principal treatment of type 1 diabetes: even in its earliest stages, is the delivery of artificial insulin via injection combined with careful monitoring of blood glucose levels using blood testing monitors…  The average glucose level for the type 1 patient should be as close to normal (80–120 mg/dl,) as is safely possible. Some physicians suggest up to (140–150 mg/dl) for those having trouble with lower values, such as frequent hypoglycemic events  Type 2 diabetes is usually first treated by - increasing physical activity, - decreasing carbohydrate intake, - losing weight These can restore insulin sensitivity even when the weight loss is modest..  The usual next step, if necessary, is treatment with oral antidiabetic drugs. Insulin production is initially only moderately impaired in type 2 diabetes, so oral medication can be used to improve insulin production. Oral medication may eventually fail due to further impairment of beta cell insulin secretion. At this point, insulin therapy is necessary to maintain normal or near normal glucose levels..  Careful control is needed to reduce the risk of long term complications. This is theoretically achievable with combinations of diet, exercise and weight loss (type 2), various oral diabetic drugs (type 2 only), and insulin use (type 1 and for type 2 not responding to oral medications, mostly those with extended duration diabetes)…  In addition, given the associated higher risks of cardiovascular disease, lifestyle modifications should be undertaken to control blood pressure and cholesterol by exercising more, smoking less, consuming an appropriate diet, wearing diabetic socks, wearing diabetic shoes, and if necessary, taking any of several drugs to reduce blood pressure… Dr. Mohamed Roshdi, MD Dr. Mohamed Roshdi, MD Many type 1 treatments include combined use of regular with NPH insulin, and/or synthetic insulin analogs (e.g, Humalog, Novolog).others include (Lantus/Levemir).  Another type 1 treatment option is the use of the insulin pump (eg,FLEXIBLE - PUMP).  A blood lancet is used to pierce the skin (typically of a finger), in order to draw blood to test it for sugar levels… Acute complications: Diabeticketoacidosis.. non ketotic hyperosmolar coma.. hypoglycemia..  Diabetic ketoacidosis : DKA is an acute and dangerous complication that is always a medical emergency. Low insulin levels cause the liver to turn to fat for fuel (i.e, ketosis.) Elevated levels of ketone bodies in the blood decrease the blood's pH, leading to DKA…  The patient in DKA is typically dehydrated, and breathing rapidly and deeply. Abdominal pain is common and may be severe.. It can cause: -Hypotension.. - Shock - Renal failure - brain edema - and DEATH Ketoacidosis is much more common in type 1 diabetes than type 2…  Hyperglycemia hyperosmolar state: Is an acute complication sharing many symptoms with DKA, but an entirely different origin and different treatment. A person with very high (usually considered to be above (300 mg/dl)) blood glucose levels, water is osmotically drawn out of cells into the blood and the kidneys eventually begin to dump glucose into the urine..  This results in loss of water and an increase in blood osmolarity. If fluid is not replaced (by mouth or intravenously), the osmotic effect of high glucose levels, combined with the loss of water, will eventually lead to dehydration…  As with DKA, urgent medical treatment is necessary, commonly beginning with fluid volume replacement. Lethargy may ultimately progress to a coma, though this is more common in type 2 diabetes than type 1..  Hypoglycemia Is abnormally low blood glucose below 70 mg/dl The patient may become agitated, sweaty, and have many symptoms of sympathetic activation of the autonomic nervous system Consciousness can be altered or even lost in extreme cases, leading to coma, seizures, or even brain damage and death.  In patients with diabetes, this may be caused by several factors, such as: - Too much or incorrectly timed insulin.. - Too much or incorrectly timed exercise.. - or Not enough food.. Hypoglycemia is treated with sugary drinks or food, and in severe cases, an injection of glucagon..  Chronic complications: Vascular disease : - Diabetic retinopathy (muscular edema) - Diabetic neuropathy (diabetic foot) - Diabetic nephropathy (renal failure) - Diabetic cardiopathy (heart failure) - Coronary artery disease (angina) - Stroke (ischemic type) - Peripheral vascular disease ( foot pain) - Diabetic myonecrosis ( muscle wasting) - The number of people with diabetes has risen from 108 million in 1980 to 422 million in 2014. The global prevalence of diabetes among adults over 18 years of age has risen from 4.7% in 1980 to 8.5% in 2014 - Saudi Arabia has one of the highest percentages of Diabetes in the world, with an estimated numberof 2,065,300 people diagnosed with the disease by 2010 Summary References 1. Step-up to medicine 5th edition. ISBN-13: 978-1975103613 2. Davidson’s Principles & Practice of Medicine 23rd edition ISBN-13: 978-0702070280 Thank You