A 7-year-old boy is brought to the emergency department due to bloody stools. The patient first developed colicky abdominal pain 2 days ago, and he had blood in a bowel movement today. His urine also appeared red. He has had no diarrhea, vomiting, or dysuria. The boy has no significant medical history, and his vaccinations are up to date. Temperature is 37.2 C (99 F), pulse is 120/min, and respirations are 20/min. The oropharynx is clear, and the neck is supple. Cardiopulmonary examination is unremarkable. The abdomen is diffusely tender with active bowel sounds. There are raised, purple-red skin lesions along the buttocks and lower extremities. Which of the following additional findings is most likely present in this patient?
IgA vasculitis (Henoch-Schönlein purpura) | |
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This patient has classic signs of Henoch-Schönlein purpura (HSP), an IgA-mediated leukocytoclastic vasculitis that is most commonly seen in children.
HSP predominantly affects the small vessels of the following organ systems:
Skin: The most common initial manifestation is palpable purpura on the buttocks and lower extremities.
Gastrointestinal (GI) tract: Intermittent colicky abdominal pain is typical. Bowel wall edema and hemorrhage can also lead to GI bleeding (eg, hematemesis, bloody stools) and serve as a lead point for intussusception.
Kidneys: Patients most commonly have gross or microscopic hematuria. Renal pathology in HSP is characterized by mesangial proliferation and IgA deposition (identical to findings seen in IgA nephropathy).
Joints: Transient or migratory arthralgia or arthritis usually occurs in the hips, knees, and ankles.
Therefore, the most likely additional finding in this patient with palpable purpura, abdominal pain, and gross hematuria is joint pain.
(Choice A) Generalized lymphadenopathy is suggestive of certain acute, viral infections such as Epstein-Barr virus (EBV) or hematologic malignancy (eg, leukemia). EBV can cause abdominal pain and a maculopapular or petechial rash in association with fever; bloody stools, hematuria, or palpable purpura are not characteristic. Hematologic malignancy can result in easy bruising and bleeding, but presentation usually includes hepatosplenomegaly and/or systemic symptoms (eg, fever, weight loss). In contrast, HSP is not associated with generalized lymphadenopathy, although localized cervical lymphadenopathy may be present due to a preceding upper respiratory infection in some patients.
(Choice B) Poststreptococcal glomerulonephritis (PSGN) presents with gross hematuria weeks after (not in conjunction with) a streptococcal infection such as impetigo, a honey-colored crusted skin rash. Moreover, PSGN is not associated with bloody stools or purpura.
(Choice C) Conjunctival injection is a classic feature of adenovirus infection and is typically associated with fever and pharyngitis, neither of which is seen here. Moreover, although certain serotypes of adenovirus can cause hematuria due to hemorrhagic cystitis or abdominal pain due to gastroenteritis, palpable purpura is not associated with any adenovirus infection.
(Choice E) Aphthous ulcers can occur with Crohn disease, which often presents with abdominal pain and bloody stools. However, hematuria and purpura would not be expected.
Educational objective:
Henoch-Schönlein purpura is an IgA-mediated leukocytoclastic vasculitis that commonly causes lower extremity palpable purpura, abdominal pain (± gastrointestinal bleeding), renal disease (eg, hematuria), and joint pain.