SYSTEMIC/AUTOIMMUNE CONDITIONS

Question 1

Q: Malignant Hyperthermia: Incidence, Genetics, Pathophysiology, Clinical, Dx, Tx [?]

Answer 1

= hypermetabolism of skeletal muscles; - AD, reduced penetrance, variable expressivity

• Epidemiology: 1 in 15,000 children, 1 in 50-100,000 adults (i.e. more common in children)
• Etiology: volatile inhalational anaesthetics, succinylcholine
• Pathophgy: AbN ryanodine receptor of skeletal muscles → Increased release OR decreased reuptake of ca2+ from sarcoplasmic reticulum → buildup of ca2+ within skeletal muscles → massive metabolic rxn
• Clinical features: (i) increased CO2, (ii) Increased O2 consumptions, (iii) muscle rigidity, (iv) metabolic + resp acidosis, (v) hyper K, (vi) myoglobinuria, (vii)fever, (viii) organ failure, (ix) DIC
• Ix: CBC, extended lytes, ABG, muscle biopsy, LDH, urine myoglobin, CL, genetic testings, caffience halthane contracture test (standard)
• Rx:
• STOP trigger agent
• ABCs
• Cool patient
• Correct hyperK
• Avoid CCB
• Dantrolene (reduces calcium loss): 2.5mg/kg q 5 minutes; max 10 doses

Question 2

Q (DO): Angioedema vs. Anaphylaxis?

Answer 2

• Angioedema: rapid dermal, subdermal or submucosal swelling

- Anaphylaxis: IgE mediated response affecting more than 1 organ system

Question 3

(DO): Role of C1 esterase inhibitor?

Answer 3

• Regulation of the complement pathway
• Controls levels of C3a, C4a, C5a
• Regulated bradykinin levels (vasodilator, increased vascular permeability
• Loss of C1 esterase inhibitor = no inhibition of bradykinin pathway → bradykinin accumulation → increased tissue vasodilaton + vascular permeability

Question 4

Q: : Ddx of Acute Angioedema <6 weeks [?]

Answer 4

• Allergy (food, drug, contact, bee stings)
• Infection
• ACE inhibitor

Rx: (i) ABCs, (ii) epinephrine, (iii) steroids, (iv) antihistamines, (v) aminophyline (vi)
avoidance of triggers

Question 5

Q: Ddx of Chronic Angioedema >6 weeks [?]

Answer 5

• Autoimmune (SLE)
• Systemic disease
• Thyroid disease
• Idiopathic
• C1 esterase inhibitor deficiency

Question 6

Q (DO): Differentiate the types of Angioedema?

Answer 6

Question 7

Q: Discuss Eosinophilic Esophagitis → CF, Etiology, Signs of esophagoscopy, Rx [?]

Answer 7

• Etiology: atopic inflammatory disease/uncontrolled immune response to antigenic stimulation → eosinophilic infiltration within esophageal mucosa.
• Clinical Features: Teen males, Food impaction / dysphagia, Feeding tolerance (peds), GERD
  exclusion of an alternative diagnosis
• Esophagoscopy Signs:
• Mucosal linear furrows
• Strictures (more common proximally)
• Trachealization - fixed tracheal rings
• Feline folds/ transient rings/stacked circiular rings
• • Surface exudates/eosinophilic microabscesses
• Mucosal fragility
• Thickened mucosa with decreased vascular pattern
• tx:
• CONSERVATIVE: dietary modifications, avoidance of food allergens, food
  allergen evaluation, hypoallergenic diet
• MEDICAL: liquid steroids, flutcasone, oral steroids, anti-acid reflux
  medication, Budesonide
• SURGICAL: FB removal, mechanical dilation

Question 8

Q: Discuss Eosinophilic Esophagitis → Histopath

Answer 8

• > 15 eosiniphils per HPF
• Granulated eosinophils
• Eosinophil microabscesses
• No erosion, ulceration or neutrophils

Question 9

Q: Four non-infectious non-neoplastic causes of lymphadenopathy [?]

Answer 9

• Kawasaki (mucocutaneous lymph node + fever + 4/5
• Kikuchi – Lymphocytosis, fever, splenomegaly (like lymphoma)
• Kimura – Idiopathic unilateral, usually submandibular adenopathy in Asians, High IgE, Eosinophilia
• Castleman’s disease – unicentric or multicentric lymphoproliferative disease
• Sarcoid
• Rosai Dorfman: granulomatous, sinus histiocytosis (looks like lymphoma); chem RT If dissmintated