Cushing's Syndrome

• Earliest feature: Loss of diurnal variation of cortisol
• High-dose dexamethasone suppression test: Differentiates pituitary adenoma vs ectopic ACTH

Adrenal Insufficiency (Addison's Disease)

• Most common cause in India: Tuberculosis
• Most common primary tumor metastasizing to adrenals: Melanoma
• Most confirmatory test: ACTH stimulation test
• Diagnostic: Low plasma cortisol (<3 mg/dL) at 8 AM + elevated ACTH (>200 pg/mL)
• Most common symptom: Asthenia (due to hypotension & hypoglycemia)

• Alpha Thalassemia: Caused by deletion of alpha genes
• HbH Disease: Deletion of 3 alpha chains

• Mobility Tests: Perio test, Fremitus test.
• Bone Evaluation: Transgingival probing.
• Halitosis Detection: Gold standard = Organoleptic analysis.
• Indices:
  • PMA Index: Gingival disease.
  • Ramfjord Index Teeth: 16, 21, 24, 36, 41, 44.
  • Merin’s Classification: Patient recall.
  • Surrogate Endpoint: Reduction in probing depth.

Pathophysiology

• Enzyme defect: Glucose-6-phosphate dehydrogenase deficiency
• Result: Impaired NADPH production → reduced glutathione → oxidative damage
• Inheritance: X-linked recessive (affects males predominantly)

Key Clinical Features

• Heinz bodies: Characteristic finding (precipitated denatured hemoglobin)
• Hemolytic episodes: Triggered by oxidative stress
• Chronic hemolysis: Usually absent between episodes
• Neonatal jaundice: May be severe

Important Clinical Points

• Estrogen does NOT induce hemolysis (unlike other conditions)
• Favism: Hemolysis after eating fava beans
• Drug-induced: Most common trigger for hemolytic crisis

Oxidative Stressors to Avoid

Medications

• Antimalarials: Primaquine, chloroquine
• Antibiotics: Sulfonamides, nitrofurantoin, chloramphenicol
• Analgesics: Aspirin (high doses), phenazopyridine
• Others: Methylene blue, naphthalene (mothballs)

Infections

• Bacterial infections
• Viral hepatitis
• Pneumonia
• Typhoid fever

Other Triggers

• Fava beans (favism)
• Diabetic ketoacidosis
• Severe illness/stress

Erythema Multiforme

• Characteristics: Erythema multiforme presents with "target" or "bull's eye" lesions, often associated with:
  • Etiologic Factors:
    • Herpes simplex infection.
    • Mycoplasma infection.
    • Drug reactions (e.g., sulfonamides, penicillins, phenylbutazone, phenytoin).

• Junctional Epithelium: Attached to enamel via hemidesmosomes; to connective tissue via external basal lamina.
• Corneocyte Formation: Keratinohyalin granules disappear, forming filaggrin.
• Langerhans Cells: Suprabasal level; antigen-presenting with Birbeck granules.
• Keratinization: Oral epithelium is 0.2 – 0.3 mm thick; may be keratinized or parakeratinized.