Rosen & Barkin's 5-Minute Emergency Medicine Consult (349 page)

• Ampicillin 50 mg/kg div. q6h IV
  
• Gentamicin 2.5 mg/kg div. q12–24h IV
  
• Metronidazole 7.5 mg/kg div. q12–48h IV
  

FOLLOW-UP

• Neonates and infants presenting with bowel obstruction
  
• Enterocolitis
  
• Ill-appearing infants should be admitted to a neonatal/pediatric intensive care unit with available pediatric surgeons
  

• Well hydrated and taking oral fluids
  
• Older children with the chief complaint of constipation
  
• Responsible parents
  
• Close follow up with a primary care provider
  

Care should be supervised by pediatric gastroenterology and/or pediatric surgery

• Presentation varies with the age of the child
  
• Continuum may vary from toxicity and enterocolitis to chronic constipation
  
• Toxic child need stabilization, antibiotics and emergent imaging and surgical intervention
  

• Amiel J, Lyonnet S. Hirschsprung disease, associated syndromes, and genetics: A review.
  J Med Genet
  . 2001;38:729–739.
  
• Kays DW. Surgical conditions of the neonatal intestinal tract.
  Clin Perinatol
  . 1996;23:353–375.
  
• Menezes M, Puri P. Long-term outcome of patients with enterocolitis complication Hirschsprung’s disease.
  Pediatr Surg Int
  . 2006;22:316–318.
  
• Moore SW, Zaahl M. Clinical and genetic differences in total colonic aganglionosis in Hirschsprung’s disease.
  J Pediatr Surg
  . 2009;44(10):1899–1903.
  
• Reding R, de Ville de Goyet J, Gosseye S, et al. Hirschsprung’s disease: A 20-year experience.
  J Ped Surg
  . 1997;32(8):1221–1225.
  
• Rudolph C, Benaroch L. Hirschsprung disease.
  Pediatr Rev
  . 1995;16:5–11.
  
• Skinner MA. Hirschsprung disease.
  Curr Prob Surg.
  1996;16:399–460.
  
• Sullivan PB. Hirschsprung’s disease.
  Arch Dis Child.
  1996;74:5–7.
  

CODES

751.3 Hirschsprung’s disease and other congenital functional disorders of colon

BASICS

• AIDS: Defined as lab evidence of HIV with CD4 <200 or AIDS defining illness—infection (e.g., cryptosporidium), malignancy (e.g., Kaposi, cervical cancer), or other (e.g., HIV wasting disease, HIV encephalopathy)
  
• Opportunistic diseases:
  
  • CD <500 cells/mm
    ³
    :
    
    • Oroesophageal candidiasis
      
    • Pneumococcal infection
      
    • Hairy leukoplakia
      
    • Immune thrombocytopenic purpura
      
  • CD4 <200 cells/mm
    ³
    :
    
    • Pneumocystis jiroveci pneumonia (PCP)
      
    • Cryptococcal infection
      
    • Disseminated tuberculosis
      
    • Cryptosporidiosis
      
    • Isosporiasis
      
    • Toxoplasmosis
      
    • Histoplasmosis
      
  • CD4 <50 cells/mm
    ³
    :
    
    • CNS lymphoma
      
    • Mycobacterium avium complex (MAC)
      
    • TB pericarditis or meningitis
      
    • Cytomegalovirus (CMV)
      
    • Cholangiopathy: Most common cause
      Cryptosporidium parvum
      

DIAGNOSIS

• Primary HIV infection: 2–6 wk after exposure:
  
  • Fever and malaise
    
  • Rash on face and trunk
    
  • Flu-like syndrome with lymphadenopathy and hepatosplenomegaly
    
  • Pharyngitis
    
  • Diarrhea
    
  • Up to 90% asymptomatic
    
• Advanced HIV disease (CD4 <200):
  
  • Fatigue
    
  • Fevers and night sweats
    
  • Weight loss/wasting
    
  • Alopecia
    
  • Chronic diarrhea
    
  • Cough
    
  • Dyspnea
    
  • Hemoptysis
    
  • Chronic low-grade headache
    
  • Altered mental status
    
  • Seizures
    
  • Dementia
    
  • Neuropathy
    
  • Painless visual loss
    
  • Skin lesions
    

• Risk factors:
  
  • Sexual promiscuity, multiple sexual partners
    
  • IV drug abuse
    
  • Men who have sex with men
    
  • Blood transfusions prior to 1985
    
  • Unprotected sex with at-risk partners
    
  • Uncircumcised
    
• Most recent CD4 count and viral load, lowest CD4 count
  
• History of or current use of antiretroviral medications
  
• Medication compliance
  
• Length of diagnosis/illness
  
• History of opportunistic infections
  
• Previous hospitalizations or ICU admissions
  

• HIV serologic tests as noted below:
  
  • There is a window of 24 wk between primary infection and seroconversion, during which tests may be negative.
    
  • DNA amplification testing can be positive within 1–2wks of infection, although may not be practical to perform from ED and requires close follow-up and counseling.
    
• Respiratory symptoms:
  
  • Chest radiograph
    
  • Arterial blood gas (ABG)
    
  • Sputum for Gram stain, AFB, and culture
    
  • Serum LDH—elevated in PCP
    
  • Blood cultures
    
• Cardiac symptoms:
  
  • Serum cardiac markers, electrolytes
    
  • CXR
    
  • ECG in cases of suspected pericarditis, effusion, or tamponade
    
  • Blood cultures if endocarditis is suspected
    
  • Drug screen for cocaine and amphetamines
    
• Neurologic symptoms:
  
  • Head CT with and without contrast
    
  • Lumbar puncture with opening pressure
    
  • CSF for glucose, protein, Gram stain and culture, cell count with differential, AFB smear, India ink stain, herpes simplex and cryptococcus antigen, and VDRL
    
• GI symptoms:
  
  • Stool for ova and parasites, Gram stain, culture, and
    Clostridium difficile
    assay
    
  • Urine analysis
    
  • For women: Urine pregnancy test, pelvic exam with wet mount, and gonorrhea/chlamydia testing
    
  • Liver functions tests, amylase, and lipase
    
  • Hepatitis serologies
    
  • Low threshold for CT abdomen/pelvis
    
  • US if biliary symptoms present
    
  • Low threshold for surgical consult, as HIV patients may not present with classic acute abdomen
    
• Fever workup:
  
  • Include aerobic/anaerobic, fungal, AFB, and MAC blood cultures
    
• Ocular symptoms:
  
  • Fluorescein staining with slit lamp exam
    

• ELISA:
  
  • Detects IgG antibody against HIV
    
  • Sensitivity and specificity ∼99%
    
  • Can be negative during the window period
    
• Western blot:
  
  • Detects IgG antibody against HIV proteins p24, gp 120, gp 41
    
  • Used to confirm a positive ELISA
    
  • Able to detect HIV during the 6 mo seroconversion period
    
• Rapid HIV testing:
  
  • Results available in 5–20 min
    
  • 4 types of tests currently available
    
  • Samples include oral swabs, whole blood, serum, or plasma
    
  • All reactive tests require confirmatory testing with western blot or ELISA
    
  • >99% specific and sensitive
    
• Absolute lymphocyte count (ALC):
  
  • Multiply WBC × percent lymphocytes
    
  • If ALC >2,000, likely CD4 >200, if ALC <1,000, likely CD4 <200
    

• CXR:
  
  • Bilateral interstitial infiltrates: PCP
    
  • Reticulonodular infiltrates: TB, KS, or fungal pneumonia
    
  • Hilar lymphadenopathy with infiltrate: TB, cryptococcosis, histoplasmosis, neoplasm
    
  • Lobar consolidation: Bacterial pneumonia
    
  • Cavitation: TB, necrotizing bacterial pneumonia, coccidioidomycosis
    
  • Normal x-ray does not rule out PCP or TB
    
• Head CT with and without IV contrast:
  
  • Multiple ring-enhancing lesions with edema in basal ganglia or cortex: Toxoplasmosis or CNS lymphoma
    
  • Subcortical nonenhancing lesions: PML
    
• Abdominal/pelvic CT:
  
  • Splenomegaly: CMV, TB
    
  • Intestinal perforation or bowel obstruction: CMV colitis, lymphoma, histoplasmosis, MAC, appendicitis, ulcer disease, KS
    
  • Cholecystitis or cholangitis: Cryptosporidium, Microsporidium, CMV
    
  • Pancreatitis: Medication-related, neoplasm, infectious