Rosen & Barkin's 5-Minute Emergency Medicine Consult (393 page)

For altered mental status, administer Narcan, glucose (ideally after Accu-Chek and thiamine)

• Establish airway, breathing, and circulation.
  
• For fluid boluses, use normal saline and avoid lactated Ringer and avoid hypotonic fluid.
  
• Initiate IV glucose at rate of 8–10 mg/kg/min to prevent catabolism:
  
  • Corresponds to D
    ₁₀
    at 1.5 times maintenance.
    
  • Do not delay glucose infusion to give a “bolus” of isotonic saline; may be given concurrently in a child in shock.
    
  • If patient is severely hypoglycemic, give IV glucose bolus of D
    ₂₅
    .
    
• Rehydrate if patient is hypoglycemic:
  
  • Restore normal acid–base balance.
    
• Administer bicarbonate if pH is <7.0:
  
  • Initiate dialysis if severe acidosis does not improve quickly.
    
• Increase urine output to help in removal of some toxins.
  
• Initially, stop all oral intake; amino acid metabolites may be neurotoxic.
  
• Treat severe hyperammonemia (≥500–600 mmol/L) with immediate dialysis or with ammonia-trapping drugs such as:
  
  • Arginine hydrochloride
    
  • Sodium benzoate
    
  • Sodium phenylacetate
    
  • Sodium phenylbutyrate
    
  • Doses vary with disease; consult metabolic physician before use.
    
• Identify and treat intercurrent or precipitating infection/illness.
  
• Consult metabolic physician when any child presents with suspected inherited metabolic disease.
  

• D
  ₂₅
  : 2–4 mL/kg IV
  
• Sodium bicarbonate: 1–2 mEq/kg IV
  
• Other disease-specific drugs, including pyridoxine and levocarnitine as indicated
  

Glucose:

• 0.9% NS at 20 mL/kg
  

Bicarbonate therapy for pH <7.0:

• Hemodialysis as needed
  

FOLLOW-UP

• Infants and children presenting with new onset of suspected inherited metabolic disease
  
• Significant urinary ketones or not tolerating oral intake
  
• ICU:
  
  • Significant altered mental status
    
  • Severe or persistent acidosis
    
  • Unresponsive hypoglycemia
    
  • Hyperammonemia
    
• Transfer to specialized pediatric center may be indicated.
  

• Normal mental status
  
• Normal hydration with unremarkable labs
  
• No evidence of significant intercurrent illness
  
• Close follow-up arranged with primary care physician
  

Neurodevelopment:

• Diet
  
• Medications
  

• Primary care physician
  
• Metabolic disease specialist
  

Watch for dehydration:

• Treat dehydration with normal saline fluid bolus:
  
  • Follow glucose level carefully; avoid hypoglycemia.
    
  • Use bicarbonate cautiously and only consider if pH <7.0.
    
  • Hemodialysis may be necessary for hyperammonemia.
    

• Alfadhel M, Al-Thihli K, Moubayed H, et al. Drug treatment of inborn errors of metabolism: A systematic review.
  Arch Dis Child
  . 2013;98(6):454–461. Published Online First: 2013 Mar 26 [Epub ahead of print].
  
• Barness LA. An approach to the diagnosis of metabolic diseases.
  Fetal Pediatr Pathol
  . 2004;23:3–10.
  
• Fernhoff PM. Newborn screening for genetic disorders.
  Pediatr Clin North Am
  . 2009;56:505–513.
  
• Leonard JV, Morris AA. Inborn errors of metabolism around time of birth.
  Lancet
  . 2000;356:583–587.
  
• Levy PA. Inborn errors of metabolism: Part 1: Overview.
  Pediatr Rev
  . 2009;30(4):131–137.
  
• Levy PA. Inborn errors of metabolism: Part 2: Specific disorders.
  Pediatr Rev
  . 2009;30(4):e22–e28.
  
• Weiner DL. Metabolic emergencies. In: Fleisher GR, Ludwig S, Henretig FM, eds.
  Textbook of Pediatric Emergency Medicine
  . 6th ed. Philadelphia, PA: Lippincott; 2010.
  
• Wolf AD, Lavine JE. Hepatomegaly in neonates and children.
  Pediatr Rev
  . 2000;21:303–310.
  

CODES

• 270.6 Disorders of urea cycle metabolism
  
• 270.9 Unspecified disorder of amino-acid metabolism
  
• 277.9 Unspecified disorder of metabolism
  

BASICS

• Idiopathic, chronic inflammatory diseases of intestines, which can involve extraintestinal sites as well.
  
• Differentiation between ulcerative colitis (UC) and Crohn's is not always clear; intermediate forms of inflammatory bowel disease (IBD) exist.
  
• May present as initial onset of disease or exacerbation of existing disease.
  
• Maintain high index of suspicion owing to frequent, subtle presentation of Crohn's disease.
  
• Pediatric considerations:
  
  • Can occur in 1st few years of life.
    
  • Extraintestinal manifestations may predominate.
    
• Differences between Crohn's and UC:
  
  • Rectum almost always involved in UC with continuous inflammation proximally.
    
  • Small intestine is not involved in UC.
    
  • Crohn's can occur anywhere from mouth to anus, often with normal GI tract segments between affected areas.
    
  • Crohn's involves transmural inflammation, whereas UC is confined to submucosa.
    
• Similarities between Crohn's and UC:
  
  • Higher rate of colon cancer with disease >10 yr.
    
  • Bimodal age distribution, with early peak between teens and early 30s and 2nd peak about age 60 yr.
    
• Crohn's disease clinical pattern:
  
  • Ileocecal: ∼40%
    
  • Small bowel: ∼30%
    
  • Colon: ∼25%
    
  • Other: ∼5%
    
• UC clinical pattern on presentation:
  
  • Pancolitis: 30%:
    
    • Most severe clinical course
      
• Proctitis or proctosigmoiditis: 30%:
  
  • Relatively mild clinical course
    
• Left-sided colitis (up to splenic flexure): 40%:
  
  • Moderate clinical course
    

• Unknown
  
• Crohn's disease and UC are separate entities with common genetic predisposition.
  
• A positive family history is very common.
  
• Multifactorial origin involving interplay among the following factors:
  
  • Genetic
    
  • Environmental
    
  • Immune
    
• Pathogenesis:
  
  • Gut wall becomes unable to downregulate its immune responses, ultimately resulting in chronic inflammation.
    
• There is no definitive evidence for the etiologic role of infectious agents.
  
• Psychogenic factors may play a role in some symptomatic exacerbations.
  

DIAGNOSIS

• Crohn's disease can present with any clinical correlates of chronic inflammatory, fibrostenotic, or fistualizing illness.
  
• UC may begin subtly or as catastrophic illness.
  
• Constitutional, GI, and extraintestinal manifestations are common with both Crohn's and UC.
  

• Constitutional:
  
  • Crohn's:
    
    • Low-grade fever
      
    • Night sweats
      
    • Weight loss
      
    • Fatigue
      
    • Pediatric: Growth or pubertal delay
      
  • UC:
    
    • Fever usually only in fulminant disease
      
    • Weight loss/fatigue
      
• GI:
  
  • Abdominal pain/tenderness—Crohn's disease:
    
    • Episodic
      
    • Periumbilical; may localize to right lower quadrant (RLQ) with ileal disease
      
    • Generalized with more diffuse intestinal involvement
      
    • Can localize to area of intra-abdominal abscesses or fistulous involvement
      
    • Tenderness and distension suggest obstruction or toxic megacolon
      
  • Abdominal pain/tenderness—UC:
    
    • More generalized than Crohn's disease
      
    • Often limited to predefecatory period
      
    • Tenderness with distension—suspect toxic dilation
      
• Stool:
  
  • Crohn's disease:
    
    • Mild, loose stool, rarely >5/day
      
    • ∼50% bloody
      
  • UC:
    
    • Diarrhea is variable, can be severe.
      
    • Vast majority are bloody, sometimes with severe hemorrhage.
      
    • Mucus
      
    • Tenesmus and urgency are common.
      
• Nausea/vomiting:
  
  • Crohn's disease:
    
    • Obstruction common with ileocolonic disease
      
  • UC:
    
    • Obstruction rare
      
    • Diminished bowel sounds with toxic dilation
      
• Liver:
  
  • Sclerosing cholangitis can be seen.
    
  • Cholelithiasis can be seen in 35–60% of Crohn's.
    
• Renal:
  
  • Nephrolithiasis
    
  • Obstructive hydronephrosis
    
• Musculoskeletal:
  
  • Peripheral arthritis/arthralgias—follows disease activity.
    
  • Pediatric—may be confused with juvenile rheumatoid arthritis, idiopathic growth failure, anorexia nervosa.