Acanthosis nigricans in diabetes mellitus

You note the shown skin disorder during a general medical evaluation. You explain to the patient they are at risk for the development of:

A) Alzheimer's disease

B) tuberculosis

C) diabetes mellitus

D) Grave's disease

E) melanoma



 The answer is C. (Diabetes mellitus) 
Although the majority of cases of acanthosis nigricans are benign and associated with obesity, the disease can represent the onset of malignancy as well as a variety of conditions related to insulin resistance.
Acanthosis nigricans has been reported in association with a number of malignancies, particular gastrointestinal cancers (e.g., gastric, hepatocellular) and lung cancer. The suspicion for malignancy increases in patients with extensive or rapidly progressive lesions, when there is mucous membrane involvement, or when there is prominent sole and palm disease.

The common finding in all non-malignancy associated cases of acanthosis nigricans is insulin resistance. This explains the relationship between this skin disorder and diseases such as diabetes mellitus, Cushing's syndrome, and hypothyroidism (most likely due to weight gain and subsequent insulin resistance), and with obesity.

A case of Necrolytic migratory erythema due to glucagonoma.

This 63-year-old woman with a 4 1/2-year history of diabetes mellitus presented with an ulcerating rash, primarily on the shins, groin, and face (Panel A); cheilitis (Panel B); and glossitis.
Her symptoms had been worsening for 4 years despite specialized wound care. In addition, she noted concurrent weight loss, depression, abdominal pain, and intractable nausea. She was taking 500 mg of metformin daily. Given her history of diabetes mellitus and the skin findings, abdominal computed tomography was performed, and glucagon levels were measured.

An enhancing, lobulated mass measuring 7 cm in diameter was found in the tail of the pancreas, and the patient's fasting glucagon level was elevated, at 890 pg per milliliter (normal range, 0 to 80). The mass was resected, and pathological examination of the specimen confirmed a diagnosis of glucagonoma.

Glucagonomas are rare neuroendocrine tumors that can cause diabetes and a rash known as necrolytic migratory erythema, which has a characteristic annular pattern of erythema with central crusting and bullae. The prognosis correlates with the stage of tumor development and the potential for resection. In this patient, 1 day after resection, the rash had faded significantly. Four weeks after discharge, the patient had normal glucose levels (while taking no medication), and the necrolytic migratory erythema had completely resolved.

Causes of osteoporotic changes in Cushing’s syndrome

Patients with Cushing’s syndrome often show osteoporotic changes.Which of the following is involved in the etiology of osteoporosis induced by Cushing’s syndrome?

• a.Decreased glucocorticoid levels that result in decreased quality of the bone
• deposited
• b.Excess deposition of osteoid
• c.Stimulation of intestinal calcium absorption
• d.Decreased PTH levels
• e.Bone fragility resulting from excess bone resorption

The answer is E.

Osteoporosis is a major problem of normal aging in both sexes but is particularly prevalent in older women. In that disease, the quality of bone is unchanged, but the balance between bone deposition and bone resorption is lost. The disease is prevalent in postmenopausal women because the protective effect of estrogens is no longer present.
Osteoporosis may also be induced by other diseases (e.g., hyperthyroidism) or drugs (e.g., alcohol and caffeine). In addition, excess glucocorticoid induces osteoporosis. For example, in Cushing’s syndrome, patients produce high levels of corticosteroids that interfere with bone metabolism. A similar pattern may be seen during prolonged steroid therapy. The result is increased bone resorption compared with bone deposition. Intestinal calcium absorption is inhibited and PTH "Parathormone" levels may be increased.

Insulin injection lipodystrophy

Many patients whit type 1 diabetes mellitus may presented with depressed areas of skin at the sites of insulin injection due to lipoatrophy......!!
Lipodystrophy or lipoatrophy is a recognized complication of Insulin injection due to loss of the adipose tissue layer at the sites of injection (prevalence of 3.6%).

Axial magnetic resonance imaging of the right thigh showed Lipoatrophy of a 14-year-old girl with a 20-month history of type 1 diabetes mellitus

The pathogenesis remains unknown, but possible mechanisms include immune reaction to insulin or excipients of the injection solution, injury from cold insulin, or trauma from repeated local injections.

Synthesis & Transport of Thyroid Hormones

The thyroid secretes 2 iodine-containing hormones: thyroxine (T4 ) and triiodothyronine (T3). The iodine necessary for the synthesis of these molecules comes from food or iodide supplements. Iodide ion is actively taken up by and highly concentrated in the thyroid gland, where it is converted to elemental iodine by thyroidal peroxidase ( See the Figure ).
The protein thyroglobulin serves as a scaffold for thyroid hormone synthesis. Tyrosine residues in thyroglobulin are iodinated to form monoiodotyrosine (MIT) or diiodotyrosine (DIT) in a process known as iodineorganification.
Within thyroglobulin, 2 molecules of DIT combine to form T4, while 1 molecule each of MIT and DIT combine to form T3. Proteolysis of thyroglobulin liberates the T4 and T3, which are then released from the thyroid. After release from the gland, T4 and T3 are transported in the blood by thyroxine-binding globulin, a protein synthesized in the liver.

This figure also show Sites of action of some antithyroid drugs. I–, iodide ion; I°, elemental iodine. Not shown: radioactive iodine (131I), which destroys the gland through radiation.

GOUT PIC

Gout of the Right Great Toe: Diffuse swelling and redness centered at the right MTP joint, but extending
over much of the foot.


Gout of the Left Great Toe: Diffuse swelling and redness centered at the left MTP joint.

Osteoporosis of aging (senile or postmenopausal osteoporosis)

Most common form of generalized osteoporosis. As a person ages, the bones lose density and become more brittle, fracturing more easily and healing more slowly. Many elderly persons are also less active and have poor diets that are deficient in protein. Females are affected more often and more severely than males, as postmenopausal women have deficient gonadal hormone levels and decreased osteoblastic activity.

 Osteoporosis of aging. Generalized demineralization of the spine in a postmenopausal woman. The cortex appears as a thin line that is relatively dense and prominent (picture-frame pattern).

Scheme for Metabolic acidosis

Metabolic acidosis is a commonly presenting feature and is often caused by diabetes, renal failure or poisoning. However, it can cause diagnostic difficulties, particularly in the acute situation when patients can be seriously ill and where the aetiology is not obvious. It is vital that its diagnosis is considered in the clinical context with attention given to history (especially of drugs) and physical signs.

Metabolic acidosis is characterised by a raised [H+] and a low / normal PCO2 (in contrast with respiratory acidosis where the PCO2 is high). A low derived bicarbonate or low plasma total CO2 accompanies the raised [H+].

The raised [H+] stimulates the respiratory centre and hyperventilation occurs with a consequent rise in PO2. Hyperventilation reduces PCO2 and hence some of the potential acid burden on the body and acts to compensate for the metabolic acidosis. Complete compensation does not occur (ie the [H+] remains elevated) and the extent of the compensation will be limited in patients with an underlying diminution in respiratory function.

Some confusion may occur in patients admitted with 'collapse' and in extremis. Cardio respiratory collapse will result in a mixed acidosis due to a peripheral metabolic acidosis due to poor perfusion and a respiratory acidosis due to poor ventilation resulting in a raised [H+] and raised PCO2.

Screening for Diabetic Retinopathy by new Fundus Camera

Hyper Vs Hypothyroidism

Eliciting Chvostek’s sign

Chvostek's sign is contraction of the muscles of the eye, mouth or nose, elicited by tapping along the course of the facial nerve. The examiner taps gently over the facial nerve in front of the ear.

This sign usually suggests hypocalcemia but can occur normally in about 25% of patients. Typically, it precedes other signs of hypocalcemia and persists until the onset of tetany. It can’t be elicited during tetany because of strong muscle contractions.
Normally, eliciting Chvostek's sign is attempted only in patients with suspected hypocalcemic disorders. However, because the parathyroid gland regulates calcium balance, Chvostek's sign may also be tested in patients before neck surgery to obtain a baseline.

Male Reproductive System: Hormone Pathways

A lecture on the hormones that play a role in the male reproductive system, with emphasis on the hormonal pathways.

USMLE ALGORITHMS: Cushing Syndrome

This video explains the complete workup of Cushing Syndrome, the causes, the diagnosis, and the full management. It is very thorough. I hope you enjoy

Trousseau sign of latent tetany

Trousseau’s sign presents as carpopedal spasm occurring after a few minutes of inflation of a sphygmomanometer cuff above systolic blood pressure "about 3 minutes inflate of cuff >SBP". Occlusion of the brachial artery causes flexion of the wrist and metacarpophalangeal joints, hyperextension of the fingers, and flexion of the thumb on the palm, producing the characteristic posture called main d’accoucheur (The Figure). Trousseau’s sign is
thought to be both sensitive and specific for hypocalcemic tetany. In addition to the obvious visual manifestations, patients with a positive Trousseau’s sign may also experience paresthesia of the fingers, muscular fasciculations or twitches of the fingers, and a sensation of muscular cramping or stiffness.

Pathophysiology:

The proposed mechanism for Trousseau’s sign is increased excitability of the nerves in the arm and forearm, ostensibly caused by hypocalcemia, which, in turn, causes the muscular contractions. These conditions are exacerbated by ischemia produced by the sphygmomanometer, resulting in the twitching that defines the sign.

Achondroplasia

Achondroplasia is an inherited disorder of bone growth. It is one of the group of disorders that are collectively called chondrodystrophies or osteochondrodysplasias.

The disorder causes a type of dwarfism that is recognized by its characteristic normal to large-sized head, shortened arms and legs (especially the upper arm and thigh), a normal-sized trunk, and waddling gait. Achondroplasia is the most common type of dwarfism.

Achondroplasia is inherited as an autosomal dominant trait. However, the majority of cases, approximately 80%, appear as spontaneous mutations. If one parent has achondroplasia, the infant has a 50% chance of inheriting the disorder. If both parents have the condition, the infant's chances of being affected increase to 75%.FOR MORE :

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Clinical Approach to Metabolic Alkalosis

History

Obtain historical data to pinpoint the nature of the disease causing metabolic alkalosis.

* Ask the patient about history of vomiting, other gastric fluid loss, and diuretic use. Loss of gastric fluid and HCl due to vomiting is the most common cause of metabolic alkalosis.

• Vomiting may be caused by pyloric stenosis or ulcers. Occasionally, it may be self-induced.
• Significant gastric fluid loss can occur via long-term nasogastric (NG) tube drainage.
• Diuretic use may lead to increased chloride losses.

* Obtain information about specific disease states such as primary hyperaldosteronism, reninism, hyperglucocorticoidism, Bartter syndrome, and deoxycorticosterone (DOC) excess syndromes.
* Because hypokalemia may lead to metabolic alkalosis, ask about the use of diuretics because these lead to potassium loss.

An algorithm for metabolic alkalosis

Physical

Increased neuromuscular excitability sometimes causes tetany or seizures. Generalized weakness may be noted if the patient also has hypokalemia. Signs and symptoms observed with metabolic alkalosis usually relate to the specific disease process that caused the acid-base disorder.

* Patients who develop metabolic alkalosis from vomiting can have symptoms related to severe volume contraction, with signs of dehydration that include tachycardia, dry mucous membranes, decreased skin turgor, postural hypotension, poor peripheral perfusion, and weight loss.
* Although diarrhea typically produces a hyperchloremic metabolic acidosis, diarrheal stools may rarely contain significant amounts of chloride, as in the case of congenital chloride diarrhea. Children with this condition present at birth with watery diarrhea, metabolic alkalosis, and hypovolemia.
* Weight gain and hypertension may accompany metabolic alkalosis that results from a hypermineralocorticoid state.

Surgical Debridement of an Infected Diabetic Foot Wound

Disease of bones,stones,abdominal groans and psychiatric moans

Primary hyperparathyroidism is described as "a common disorder of mineral metabolism characterized by incompletely regulated, excessive secretion of parathyroid hormone from one or more of the parathyroid glands"

The signs and symptoms of primary hyperparathyroidism are those of hypercalcemia. They are classically summarized by the mnemonic "stones, bones, abdominal groans and psychiatric moans".

* "Stones" refers to kidney stones, nephrocalcinosis, and diabetes insipidus (polyuria and polydipsia). These can ultimately lead to renal failure.
* "Bones" refers to bone-related complications. The classic bone disease in hyperparathyroidism is osteitis fibrosa cystica, which results in pain and sometimes pathological fractures. Other bone diseases associated with hyperparathyroidism are osteoporosis, osteomalacia, and arthritis.
* "Abdominal groans" refers to gastrointestinal symptoms of constipation, indigestion, nausea and vomiting. Hypercalcemia can lead to peptic ulcers and acute pancreatitis.
* "Psychiatric moans" refers to effects on the central nervous system. Symptoms include lethargy, fatigue, depression, memory loss, psychosis, ataxia, delirium, and coma.

The German description of the same symptoms is "Stein-, Bein- und Magenpein", literally "stone, leg, and stomach-pain".

In 1990, A National Institutes of Health (NIH) consensus panel defined renal stones in patients with primary hyperparathyroidism as an absolute indication for parathyroidectomy.

2-year-old woman  underwent parathyroidectomy for primary hyperparathyroidism. Sonogram of left kidney shows multiple calculi (arrows).