Rosen & Barkin's 5-Minute Emergency Medicine Consult (546 page)

• Herald patch:
  
  • Nummular eczema
    
  • Tinea corporis
    
• Secondary eruption:
  
  • Secondary syphilis
    
  • Drug eruption
    
  • Guttate psoriasis
    
  • Kaposi sarcoma
    
  • Lichen planus
    
  • Occult malignancy
    
  • Scabies
    
  • Seborrheic dermatitis
    
  • Tinea versicolor
    
  • Dermatomyositis
    
  • Cutaneous lymphoma
    
  • Lupus
    

TREATMENT

None required

• Pityriasis is self-limiting
  
• Pruritus may improve after treatment with steroids, antihistamines, and, interestingly, erythromycin
  

• Diphenhydramine: Adult: 25–50 mg PO QID (peds: 5 mg/kg/d div. QID)
  
• Erythromycin: 400 mg (peds: 10 mg/kg) PO QID
  
• Hydrocortisone: 1% cream TID
  
• Prednisone: 15–40 mg (peds 0.25–0.5 mg/kg) daily
  

• Diphenhydramine: Adult: 25–50 mg PO QID (peds: 5 mg/kg/d div. QID)
  
• Hydrocortisone: 1% cream TID
  

• Prednisone: 15–40 mg (peds 0.25–0.5 mg/kg) daily
  
• Erythromycin: 400 mg (peds: 10 mg/kg) PO QID
  

FOLLOW-UP

Pityriasis rosea is a self-limited disease; admission is not required

Patients with a clear diagnosis of pityriasis rosea may be discharged

Severe refractory pruritus may require dermatology follow-up

• With primary care provider as needed
  
• Symptoms usually resolve over 1–2 mo
  

• Pityriasis is usually limited to the proximal extremities and trunk. Consider alternative diagnoses beyond
  inverse pityriasis
  in a patient with mucous membrane or distal extremity involvement.
  
• Consider alternative diagnoses in those patients who appear toxic or have atypical presentations.
  

• Browning JC. An update on pityriasis rosea and other similar childhood exanthems.
  Curr Opin Pediatr
  . 2009;21:481–485.
  
• Chuh AA, Dofitas BL, Comisel GG, et al. Interventions for pityriasis rosea.
  Cochrane Database Syst Rev
  . 2007;(2):CD005068.
  
• Drago F, Broccolo F, Rebora A. Pityriasis rosea: An update with a critical appraisal of its possible herpesviral etiology.
  J Am Acad Dermatol
  . 2009;61:303–318.
  
• Stulberg DL, Wolfrey J. Pityriasis rosea.
  Am Fam Physician
  . 2004;69:87–91.
  

CODES

696.3 Pityriasis rosea

BASICS

• Hemorrhage at the decidual–placental interface leading to complete or partial separation of the normally implanted placenta before delivery of the fetus
  
• Incidence/prevalence:
  
  • ∼1% of all pregnancies
    
  • 30% of bleeding episodes in the 2nd half of pregnancy
    
  • 15% of all fetal deaths
    
  • Neonatal death in 10–30% of cases
    
  • 6% of all maternal mortality
    
• Synonym(s): Abruptio placentae, accidental hemorrhage (in UK)
  

• Primary cause unknown
  
• Vascular injury with dissection of blood into the decidua basalis or mechanical shearing between the placenta and uterus leading to bleeding and clot formation
  
• More severe cases lead to:
  
  • Development of disseminated intravascular coagulation (DIC)
    
  • Maternal–fetal compromise
    
• Research suggests that the majority of abruptions are due to chronic processes:
  
  • Inflammatory changes in the placenta
    
  • Manifestation of ischemic placental disease
    
• Acute abruption can occur due to:
  
  • Trauma
    
  • Rapid uterine decompression
    
  • Placenta implantation over a uterine anomaly or fibroid
    
• Multiple known risk factors:
  
  • Previous abruption (10–20% recurrence risk)
    
  • Maternal hypertension (>140/90) and preeclampsia
    
  • Increased parity and maternal age
    
  • Multiple gestation
    
  • Fibroids or other uterine/placental abnormalities
    
  • Tobacco use
    
  • Cocaine abuse
    
  • Trauma
    
  • Premature rupture of membranes, particularly if associated with chorioamnionitis or oligohydramnios
    
  • Rapid uterine decompression:
    
    • Polyhydramnios with membrane rupture
      
    • Rapid delivery of 1st twin
      
  • Elevated 2nd trimester maternal serum α-fetoprotein
    
  • Thrombophilias
    
  • Maternal race:
    
    • More common among African American and Caucasian women
      
    • Incidence increasing more rapidly among African American women
      

DIAGNOSIS

• 20+ wk of pregnancy
  
• Vaginal bleeding (>80%,
  usually painful
  )
  
• Abdominal or back pain (>50%)
  
• Uterine cramps, tenderness, frequent contractions, or tetany
  
• Nausea, vomiting
  
• Otherwise unexplained preterm labor
  
• History of recent trauma should be elicited
  
• Recent drug use, particularly cocaine or other sympathomimetics
  
• Prior abruption or other risk factors
  
• Estimated gestational age
  
• Prenatal care history
  

• Signs of
  hypotensive shock
  may be present
  
• Uterine tenderness frequently present
  
• Vaginal bleeding (absent in 20–25%)
  
• Petechiae, bleeding, and other signs of DIC
  
• Decreased fetal heart tones and movement
  
• Fetal bradycardia or nonreassuring fetal heart rate tracings
  

• Large-bore IV access
  
• Blood type, Rh, and cross-match
  
• Rapid hemoglobin determination
  
• Determine fetal heart tones by Doppler
  
• Fetal monitoring to detect signs of early fetal distress
  
• Uterine tocographic monitoring
  

Diagnosis is primarily clinical, supportive tests include

• Blood type and Rh
  
• CBC
  
• PT/PTT
  
• Fibrinogen levels (normally 450 in latter half of pregnancy) and fibrin split products
  
• Fibrinogen <200 mg/dL and platelets <100,000/μL highly suggestive of abruption
  
• Kleihauer–Betke if mother Rh-negative (significant fetal-to-maternal hemorrhage more likely in traumatic abruption)
  

• US demonstrates evidence of abruption in only 50% of cases (false-negative common)
  
• MRI sensitive but impractical
  
• If abdomen/pelvis CT scan done as part of maternal trauma evaluation, evidence of abruption may be visible (must ask the radiologist to evaluate specifically)
  

• Placenta previa
  
• Bleeding during labor
  
• Vaginal or cervical lacerations
  
• Uterine rupture
  
• Preterm labor
  
• Ovarian torsion
  
• Pyelonephritis
  
• Cholelithiasis/cholecystitis
  
• Appendicitis
  
• Other blunt intra-abdominal or pelvic injuries