Endocrine

Diabetic Ketoacidosis (DKA)

Symptoms: Excessive urination, extreme thirst, dehydration, deep labored breathing (Kussmaul respirations), drowsiness, potential coma

• Elevated anion gap, often leading to electrolyte imbalances, especially potassium (requires cardiac monitoring)

Treatment:

• Fluid resuscitation with normal saline; introduce dextrose when blood glucose falls below 250
• IV insulin administration until anion gap normalizes
• Potassium supplementation if levels drop below 4.5 (monitor closely, as insulin shifts potassium into cells)
• Bicarbonate therapy if pH falls below 7.0

Hyperosmolar Hyperglycemic State (HHS)

Triggered by various factors (burns, stroke, infections, certain medications), commonly seen in type 2 diabetes

• No significant acidosis (absence of ketones)
• Altered mental status
• Severe hyperglycemia >600 mg/dL
• Bicarbonate levels >20

Treatment:

• Aggressive fluid replacement (deficit of 9-12 liters)
• Correction of electrolyte disturbances
• Gradual glucose reduction
• Address underlying cause

Antidiuretic Hormone (ADH) Disorders

Diabetes Insipidus (DI)

Inadequate ADH (“ADds Hydration Hormone”) results in excessive water loss

• Causes:
  • Reduced production: Pituitary tumor, head trauma, cerebral aneurysm, medications (phenytoin, lithium)
  • Decreased sensitivity: Polycystic kidney disease, chronic kidney infections (pyelonephritis)
• Inability to concentrate urine leads to excessive urination and dehydration

Treatment: Fluid replacement and ADH supplementation (desmopressin acetate)

Syndrome of Inappropriate ADH (SIADH)

Excessive ADH secretion leads to fluid retention and dilutional hyponatremia.

Common Causes: Certain cancers, infections, strokes.
Treatment: Diuretics (e.g., furosemide), controlled sodium correction with hypertonic saline.

Thyroid Disorders

Thyroid Storm

Life-threatening and progresses rapidly—fatal within hours if untreated.
Triggers: Stress, diabetic ketoacidosis (DKA), trauma, myocardial infarction (MI).

Symptoms (“Hot”):

• Severe hyperglycemia
• Rapid heart rate
• Anxiety and tremors
• High fever

Treatment:

• Reduce fever
• Block thyroid hormone synthesis (propylthiouracil – PTU)
• Address underlying trigger
• Supportive care

Myxedema Coma

Severe hypothyroidism, often in patients with pulmonary or cardiovascular disease.

Symptoms (“Cold”):

• Elevated TSH
• Low blood sugar
• Slow breathing (hypoventilation)
• Slow heart rate (bradycardia)
• Low blood pressure
• Hypothermia with shivering

Treatment:

• Gentle fluid replacement
• Passive rewarming
• IV thyroid hormone therapy

Cortisol

Adrenal Crisis

Acute deficiency of cortisol, typically in individuals with chronic adrenal insufficiency (e.g., Addison’s disease).

Triggers: Abrupt corticosteroid withdrawal, head trauma.

Treatment:

• IV hydrocortisone
• Electrolyte stabilization

The 5 S’s of Adrenal Crisis:

1. Sudden severe pain
2. Syncope (fainting)
3. Shock
4. Critically low blood pressure
5. Severe nausea, vomiting, and diarrhea

Pheochromocytoma

Adrenal medulla tumor causing excessive catecholamine release.

Key Sign: Severe, persistent hypertension.
Treatment: Alpha-blockers (e.g., nitroprusside), surgical tumor removal.

Cushing’s Syndrome

Excess cortisol production—think of it as having a “cortisol cushion.” Also linked to excess androgens.

Causes:

• Adrenal or pituitary adenoma
• Long-term steroid use
• HPA Axis Dysfunction:
  • Hypothalamus releases corticotropin-releasing hormone (CRH)
  • CRH stimulates the pituitary to release ACTH
  • ACTH triggers the adrenal glands to produce cortisol

Cortisol Basics:

• Lipid-soluble hormone
• Majority bound to cortisol-binding globulin (CBG), with only ~5% active

Signs & Symptoms – “STRESSED”

• Skin fragile
• Truncal obesity
• Rounded face
• Elevated blood pressure
• Striae on abdomen and limbs
• Sugar levels high
• Excessive body hair growth
• Dorsocervical fat pad (“buffalo hump”)
• Depression

Pediatric Manifestations:

• Delayed puberty
• Gynecomastia

Effects of High Cortisol:

• Hypertension (due to increased catecholamine sensitivity)
• Tissue Breakdown: Muscle, bone, and skin degradation
• Hyperglycemia & Central Obesity:
  • Cortisol increases glucose → Triggers insulin release → Stimulates fat storage
• Reproductive Dysfunction:
  • Inhibits gonadotropin-releasing hormone (GnRH) → Impacts ovarian/testicular function
• Immunosuppression: Increased infection risk

Diagnosis:

• 24-hour urine cortisol test
• Evening cortisol blood test
• Dexamethasone suppression test
• ACTH plasma levels

Treatment:

• Gradual tapering of exogenous steroid use
• Surgical removal of adrenal or pituitary tumors

Addison’s Disease

Deficiency of cortisol—think “need to ADD cortisol.”

Symptoms – “STEROID”

• Sodium & sugar depletion (low Na+, hypoglycemia)
• Tiredness & muscle weakness
• Electrolyte imbalances (↑ K+, ↓ Na+)
• Reproductive changes (irregular periods, low libido)
• Orthostatic hypotension
• Increased skin pigmentation (bronzing)
• Diarrhea & depression

Treatment:

• Corticosteroid replacement therapy (e.g., hydrocortisone, prednisone)

Adrenal Gland Failure

(Also known as Primary Adrenal Insufficiency)

A condition where the adrenal glands are unable to produce sufficient glucocorticoids, mineralocorticoids, and androgens.

Causes:

1. Adrenal Dysgenesis – Congenital adrenal hypoplasia or improper development
2. Defective Steroidogenesis – Issues with cholesterol or steroid biosynthesis
3. Adrenal Gland Destruction – Often due to disease (e.g., tuberculosis)

Treatment:

• Glucocorticoid Replacement: Hydrocortisone (TID)
• Mineralocorticoid Replacement: Fludrocortisone (daily)

Caution:

Undertreatment Signs:

• Fatigue, muscle weakness, appetite loss
• Darkened skin pigmentation
• Low blood pressure
• Low sodium, high potassium
• Hypoglycemia

Overtreatment Signs:

• Weight gain
• Hypertension
• High blood sugar
• Growth suppression
• Fragile skin, bruising, poor wound healing
• Stretch marks and osteoporosis

Environmental Factors, Substance Misuse, Poisoning, and Overdose

Common Toxic Agents and Antidotes

Toxic Agent	Corresponding Antidote
Acetaminophen	N-acetylcysteine (Mucomyst/Acetadote)
Heavy Metal Poisoning	Dimercaprol (BAL in oil)
Calcium Channel Blocker Overodose	Calcium (chloride or gluconate)
Iron Toxicity	Deferoxamine
Benzodiazepine Overdose	Flumazenil (Romazicon)
Methanol/Ethylene Glycol Poisoning	Ethanol/Fomepizole (Antizol)
Opioid Overdose	Naloxone (Narcan)
Beta Blocker Toxicity	Glucagon
Warfarin Reversal	Vitamin K
Heparin Overdose	Protamine Sulfate
Carbon Monoxide Poisoning	High-flow Oxygen

Pearls

• Rabies Transmission: Bats are the leading vector. Any bite, direct contact, or suspected exposure warrants prophylaxis.
• Hypothermia & ECG: Look for J-waves (Osborn waves) as a diagnostic marker.
• Brown Recluse Spider Bites: Can lead to disseminated intravascular coagulation (DIC).
• Lyme Disease Complications:
  • Neurological: Headaches, cranial neuropathies (esp. CN VII), radiculoneuritis, lymphocytic meningitis.
  • Cardiac: Lyme carditis.
  • Musculoskeletal: Lyme arthritis.

Acetaminophen Toxicity

Liver Damage Mechanisms:

1. Clotting factor depletion → Increased bleeding risk/DIC.
2. Impaired glycogen storage → Hypoglycemia.
3. Ammonia accumulation → Hepatic encephalopathy.

Treatment:

• Antidote: Acetylcysteine.
• Labs: Measure serum acetaminophen levels within 4 hours post-ingestion.

Amphetamine Overdose

Symptoms:

• Restlessness, tremors, seizures.
• Tachycardia, hypertension.

Mydriasis:

Pupil dilation.

Formication:

Hallucination of bugs crawling on skin.

Benzodiazepine Overdose

Effects (CNS Depression):

1. Low blood pressure.
2. Cardiac dysrhythmias.
3. Respiratory suppression.

Treatment:

• Antidote: Flumazenil (Romazicon) – use cautiously due to seizure risk.
• Supportive Care: Activated charcoal, sodium bicarbonate.
• Airway Protection: Intubation if needed.

Bite Management

• Antibiotics: Required for cat bites; optional for dog bites.
• Rabies Risk (Bats, Foxes, Raccoons):
  • Immediate protection: Rabies immunoglobulin.
  • Long-term immunity: Vaccine series.

Carbon Monoxide Poisoning

• Affinity for Hemoglobin: Strongly binds to hemoglobin, preventing oxygen transport, but does not readily diffuse across lung tissue.
• Characteristic Sign: Cherry-red skin discoloration.
• Symptoms: Dizziness, chest pain (CP), cardiotoxic effects with ST-segment changes.
• Diagnostic Test: Carboxyhemoglobin levels.
• Elimination Half-Life: 4.5 hours; complete clearance within 24–36 hours.
• Treatment: Administer 100% oxygen, preferably through hyperbaric oxygen therapy for faster clearance.
• Prevention & Education:
  • Recognize exposure sources.
  • Identify early symptoms (e.g., headaches).
  • Install and maintain carbon monoxide detectors.

Cocaine Toxicity

• CNS Overstimulation: Excessive catecholamine release, inhibits dopamine reuptake.
• Symptoms:
  • Dilated pupils (mydriasis)
  • Seizures, chest pain (CP), arrhythmias (nitroglycerin is safe)
• Caution: Avoid β-blockers—hypertension and tachycardia are driven by CNS activation, not primary cardiac dysfunction.
• Treatment: Benzodiazepines for CNS suppression.

Cyanide Poisoning

• Source: Inhalation from fire smoke exposure (off-gassing).
• Mechanism:
  • Cellular asphyxiation—blocks mitochondrial function → halts ATP production → cardiac failure → shock, acidosis, and cardiac/respiratory arrest.
• Symptoms: Severe respiratory distress, headache, palpitations, dizziness, flushed (rose-colored) skin.
• Diagnosis: Venous blood gas analysis.
• Treatment:Cyanide Antidote Kit
  • Amyl nitrate (can be inhaled inside a non-rebreather mask)
  • IV sodium nitrite (10 mL, 3%)
  • IV sodium thiosulfate (40 mL, 25%)

Digoxin Toxicity

• Effects: Inhibits sodium-potassium pump, leading to hyperkalemia.
• Classic Sign: Yellow-tinged vision (“halos”).
• Treatment: Digibind (digoxin-specific antibody), reserved for life-threatening cases.

Ethanol (ETOH) Toxicity

• Complication: Severe hypoglycemia.
• Delirium Tremens (DTs):
  • Early signs: 6–8 hours after last drink.
  • Severe manifestations: 12–72 hours post-ingestion.
  • Priority: Safety measures to prevent injury.
• Wernicke-Korsakoff Syndrome:
  • Cause: Thiamine (Vitamin B1) deficiency—brain cannot metabolize glucose without it.
  • Critical Intervention: Administer thiamine before glucose.

Frostbite

• Rewarming Protocol:
  • Use warm water (37°–39°C).
  • Avoid hot water and rubbing.
  • Thaw until skin becomes purple and soft (15–30 minutes).
• Severe Cases: May require tPA or heparin to prevent/reduce vascular thrombosis.

Hallucinogen Toxicity

• Primary Concern: Airway management due to altered mental status.

Heat Stroke

• Diagnosis: Core body temperature via rectal measurement.
• Treatment:Rapid cooling (until shivering begins)
  • Preferred Methods:
    • Ice water immersion
    • Ice packs applied to neck, axillae, and groin
    • Spraying cool water and using fans to promote evaporative cooling

Iron Toxicity

• Effect: Causes significant gastrointestinal damage, leading to pain and bleeding.

Stages of Poisoning:

1. Acute GI Distress: Severe vomiting, abdominal pain, and bloody diarrhea.
2. Transient Improvement: Symptoms temporarily subside, creating a false sense of recovery.
3. Systemic Deterioration: Cardiovascular collapse, shock, and massive gastrointestinal hemorrhage.

Treatment:

• Deferoxamine (iron chelator)
• Activated charcoal (limited effectiveness for iron)
• Gastric lavage (controversial efficacy)

Lithium Toxicity

• Cause: Often due to dehydration, as lithium is processed through the kidneys.
• Symptoms:
  • Ataxia (loss of coordination)
  • Nystagmus (involuntary eye movements)
  • Seizures
• Treatment: Aggressive hydration to promote lithium excretion.

Radiation Exposure

Types of Radiation:

Alpha Particles:

• Cannot be blocked by paper, wood, or concrete.
• Effects: Long-term health risks depend on exposure level; causes superficial skin injury.

Beta Particles:

• Blocked by paper, but not by wood, brick, or concrete.
• Effects: Can cause local burns and internal harm if inhaled or ingested.

Gamma Radiation:

• Penetrates paper and wood, but not concrete.
• Effects: Leads to localized injury and can cause radiation sickness.

Neutrons:

• Penetrates paper, wood, and concrete due to being electrically neutral.
• Effects: Causes deep tissue and bone damage.

Initial Stabilization Steps:

1. Assume contamination in the absence of specific radiological testing.
2. Prioritize ABCs (airway, breathing, circulation).
3. Decontamination: Remove clothing and wash skin—this can eliminate 90% of external contaminants and prevent further internal absorption.

Outcomes by Syndrome Type:

• CNS Syndrome: Altered mental status and seizures—fatal within 5 days.
• Hematopoietic Syndrome: Blood cell depletion—recovery may take weeks to 2 years.
• GI Syndrome: Gastrointestinal effects—typically full recovery.
• Cutaneous Burns: Skin injuries—usually heals completely.

Salicylate (Aspirin) Toxicity

• Effect: Damages the GI lining, increasing the risk of bleeding.
• Key Sign: Tinnitus (ringing in the ears).

Symptoms:

• Seizures
• Mental confusion
• Elevated body temperature (hyperthermia)
• Pulmonary edema
• Kidney failure

Treatment:

• Hyperventilation to correct metabolic acidosis.
• Sodium bicarbonate to alkalinize urine and promote excretion.
• Activated charcoal to reduce further absorption.

Snake Bites

Types of Snakes:

• Vipers: Cause swelling and blood clotting issues.
• Coral Snakes: Deliver a neurotoxin that affects the nervous system.

First Aid Measures:

1. Keep the affected limb immobilized at or below heart level.
2. Mark the swelling’s edges to track progression.
3. Avoid ice—it can worsen tissue damage.
4. Administer antivenin within 4 hours for best results.

Antivenin Information:

• Universal antivenins are available for common venomous pit viper bites.
• For non-U.S. snakebites, contact poison control immediately for guidance.

Tricyclic Antidepressant (TCA) Toxicity

Key Symptoms – “Three C’s”:

1. Cardiac: Dangerous arrhythmias (SVT, VT, QRS widening)
2. Convulsions: Seizures, tremors
3. Coma: Altered level of consciousness (LOC)

Highly toxic – even small overdoses can be fatal.

Mechanism of Toxicity:

• Anticholinergic effects → Blocks parasympathetic (ACH) signals
• α-Adrenergic effects → Disrupts sympathetic (fight-or-flight) function

Other Symptoms:

• Rapid heart rate (tachycardia)
• Low blood pressure (hypotension)
• Neurological impairment (confusion, unconsciousness)

Treatment Approach:

• Supportive care (maintain airway, breathing, circulation)
• Continuous cardiac monitoring due to high arrhythmia risk
• Hospital observation for delayed complications