Wallach's Interpretation of Diagnostic Tests: Pathways to Arriving at a Clinical Diagnosis (41 page)

   Urinalysis: RBCs, casts, and slight protein in 25–50% of patients. The renal picture varies from minimal urinary abnormalities for years to end-stage renal disease within months. Gross hematuria and proteinuria are uncommon.

   Hematology: coagulation tests are normal.

   Core laboratory: BUN and creatinine may be increased.

Suggested Reading

Trapani S, Micheli A, Grisolla F, et al. Henoch Schönlein Purpura in childhood: epidemiological and clinical analysis of 150 cases over a 5-year period and review of the literature.
Semin Arthritis Rheum.
2005;35:143–153.

KAWASAKI SYNDROME (MUCOCUTANEOUS LYMPH NODE SYNDROME)

   Definition

   Kawasaki syndrome is a variant of childhood polyarteritis of unknown etiology, with a high incidence of coronary artery complications.

   Laboratory Findings

   Histology: diagnosis is confirmed by histologic examination of the coronary artery (same as for polyarteritis nodosa).

   Hematology: anemia (approximately 50% of patients). Leukocytosis (20,000–30,000/μL) with shift to left occurs during 1st week; lymphocytosis appears thereafter, peaking at the end of the 2nd week, and is a hallmark of this illness. Increased ESR.

   CSF findings: increased mononuclear cells with normal protein and sugar.

   Urinalysis: increased mononuclear cells; dipstick negative.

   Joint fluid findings: increased white blood cell (WBC) count (predominantly PMNs) in patients with arthritis.

   Core laboratory: laboratory changes due to AMI. Acute-phase reactants are increased (e.g., CRP, α-1-antitrypsin); these usually return to normal after 6–8 weeks.

TAKAYASU SYNDROME (ARTERITIS)

   Definition