Rosen & Barkin's 5-Minute Emergency Medicine Consult (420 page)

CODES

732.1 Juvenile osteochondrosis of hip and pelvis

BASICS

• Neoplasms of WBCs that have undergone a malignant transformation
  
• Hyperleukocytosis:
  
  • Occurs with WBC >100,000/mm
    ³
    
  • Leads to occlusions of small vessels primarily in brain or lungs
    
  • Present with confusion, stupor, or shortness of breath
    

• Overproduction of granulocytic WBCs (neutrophils)
  
• Neutrophil function preserved
  
• Thrombocytosis
  
• Basophilia
  
• Philadelphia chromosome present in bone marrow of >95%
  

• Most common leukemia in adults
  
• Overproduction of monoclonal lymphocytes
  
• Cells accumulate in lymph nodes, bone marrow, liver, spleen
  
• Particularly prone to herpes virus infections
  

• Proliferation of undifferentiated immature cells:
  
  • Acute myelogenous leukemia (AML)—immature myeloid cells
    
  • Acute lymphocytic leukemia (ALL)—immature lymphoid cells (blasts)
    
• Rapidly fatal
  

• Cause unknown
  
• Familial clustering in chronic lymphocytic leukemia (CLL)
  
• Increased incidence of AML, ALL, and chronic myelogenous leukemia (CML) with ionizing radiation
  

• Usually have ALL:
  
  • Most common pediatric cancer
    
• 60–80% remission in those who are standard risk
  
• Better overall prognosis, except if <1 yr of age
  
• May develop leukostasis at lower levels
  
• Allopurinol dose is 3 mg/kg.
  
• Ceftazidime dose is 50 mg/kg.
  

• 90% of leukemias are AML or ALL.
  
• Myeloid leukemias are more common.
  
• CLL is very rare in pregnancy.
  
• Chemotherapeutics may cause birth defects and/or preterm labor.
  
• Same prognosis as nonpregnant; do not delay therapy.
  
• Transfuse earlier than nonpregnant; keep hemoglobin >9.8 mg/dL.
  

More likely to present with CLL and CML

DIAGNOSIS

• Asymptomatic
  
• Fatigue
  
• Weight loss
  
• Left upper quadrant pain, tenderness
  
• Abdominal fullness
  
• Splenomegaly (most common)
  
• Later stage:
  
  • Headaches
    
  • Bone pain
    
  • Arthralgias
    
  • Fever
    
  • Leukotactic symptoms:
    
    • Dyspnea
      
    • Drowsiness
      
    • Confusion
      

• Asymptomatic
  
• Fatigue
  
• Lethargy
  
• Weight loss
  
• Lymphadenopathy
  
• Splenomegaly
  
• Hepatomegaly
  

• Fever
  
• Fatigue
  
• Pallor
  
• Headache
  
• Angina
  
• Congestive heart failure, dyspnea on exertion
  
• Bone pain
  
• Granulocytic sarcoma (isolated mass of leukemic blasts)
  
• Easy bleeding (thrombocytopenia):
  
  • Petechiae
    
  • Ecchymosis
    
  • Epistaxis
    
  • Hemorrhage
    
• Infections (granulocytopenic)
  
• Organ involvement with advanced ALL:
  
  • Lymphadenopathy
    
  • Hepatomegaly
    
  • Splenomegaly
    
  • Leukemic meningitis:
    
    • Headache
      
    • Nausea
      
    • Seizures
      

• Radiation exposure
  
• Exposure to alkylating agents
  
• Recent viral infection, particularly Epstein–Barr
  

• Signs of bleeding (petechiae, purpura)
  
• Hepatomegaly and splenomegaly
  
• Presence of chloromas (AML blast tumors)
  
• Sausage-like hemorrhagic retinal veins are pathognomic for hyperviscosity.
  

• CBC/platelets:
  
  • CML:
    
  • WBC range, 10,000–1 million/mm
    ³
    
  • Neutrophils predominate.
    
  • Thrombocytosis in 50%
    
• CLL:
  
  • Absolute lymphocytosis >5,000
    
  • WBC range, 40,000–150,000/mm
    ³
    
• Acute leukemia (AML/ALL):
  
  • Anemia
    
  • Thrombocytopenia
    
  • Elevation/depression of WBCs
    

• Electrolytes, BUN, creatinine, glucose, calcium
  
• Uric acid level:
  
  • Frequently elevated, especially in ALL
    
• Lactate dehydrogenase:
  
  • Increased in acute leukemias
    
• Coagulation profile:
  
  • PT/PTT, fibrinogen, fibrin-split products
    
  • If disseminated, suspect intravascular coagulation.
    
• Blood/urine cultures if fever
  
• Arterial blood gases/pulse oximetry for shortness of breath
  

CXR for infectious workup

• Bone marrow biopsy:
  
  • Required to make diagnosis
    
  • CML—hypercellular with myeloid hyperplasia
    
  • CLL—lymphocytosis (30–100%)
    
  • Acute leukemia—hypercellular with blast cells, which replace normal marrow
    
• Leukocyte alkaline phosphatase test:
  
  • Decreased in neutrophils in CML
    
• Ph1 chromosome present in CML
  

• CML:
  
  • Lymphoma
    
  • Myeloproliferative syndromes
    
  • Systemic lupus erythematosus
    
  • Infection—bacterial, fungal, mycobacterial
    
• CLL:
  
  • Pertussis
    
  • Infectious lymphocytosis
    
  • Cytomegalovirus
    
  • Epstein–Barr virus/mononucleosis
    
  • Hepatitis
    
  • Rubella
    
• Acute leukemia:
  
  • Aplastic anemia
    
  • Leukemoid reactions to infections
    

TREATMENT

• 100% oxygen for hypoxia/shortness of breath
  
• IV access with 0.9% NS
  
• Initiate platelet transfusion for severe bleeding from thrombocytopenia.
  
• Begin broad-spectrum antibiotics for fever and granulocytopenia.
  
• Treat disseminated intravascular coagulation (see “Disseminated Intravascular Coagulation”).
  

• Treat leukostasis:
  
  • Rehydrate with 500-mL bolus (20 mL/kg) IV 0.9% NS
    
  • Administer acetazolamide to alkalinize urine.
    
  • Initiate allopurinol.
    
  • Arrange for leukapheresis.
    
  • Whole-brain radiation or dexamethasone for CNS effects
    
  • Administer hydroxyurea for CML: 20–30 mg/kg single dose daily
    
• Transfuse packed RBCs for symptomatic anemia:
  
  • May require irradiated, filtered, and HLA-type–specific blood
    
• Post-ED treatment:
  
  • CLL:
    
    • Chemotherapy
      
    • Prednisone for immune-mediated thrombocytopenia
      
    • Radiation to localized nodular masses/enlarged spleen
      
  • CML:
    
    • Interferon therapy
      
    • Chemotherapy
      
    • Bone marrow transplantation
      
  • ALL:
    
    • Chemotherapy
      
    • CNS prophylaxis with intrathecal–methotrexate/cranial radiation
      
    • Bone marrow transplantation
      
  • AML:
    
    • Chemotherapy
      
    • Bone marrow transplantation
      

• Aggressive IVF, start with normal saline, then alkalinize
  
• Packed RBC and platelets as needed
  

• Ceftazidime if febrile
  
• Allopurinol or rasburicase and diuretics if at risk for tumor lysis