severe right lower quadrant

[Asclepius1]

A febrile 12-year-old child presents with severe right lower quadrant
pain that is interpreted by the attending physician as acute appendicitis.
The patient has also been complaining of joint pain. At laparotomy, the
surgeon notes that the appendix is normal; however, the mesenteric lymph nodes are markedly enlarged and contain focal areas of microabscess formation on cut section. This patient is most likely

A. an asthmatic
B. deficient in C1 esterase inhibitor activity
C. HLA-B27 positive
D. leukopenic
E. serologically positive for toxoplasmosis

[Asclepius1]

Is it HLA-B27 some kind of inflammatory disease

[FreeSpirit]

Originally Posted by Anonymous

A febrile 12-year-old child presents with severe right lower quadrant
pain that is interpreted by the attending physician as acute appendicitis.
The patient has also been complaining of joint pain. At laparotomy, the
surgeon notes that the appendix is normal; however, the mesenteric lymph nodes are markedly enlarged and contain focal areas of microabscess formation on cut section. This patient is most likely

A. an asthmatic
B. deficient in C1 esterase inhibitor activity
C. HLA-B27 positive
D. leukopenic
E. serologically positive for toxoplasmosis

The correct answer is C.Yersinia enterocolitica is the pathogen producing this clinical syndrome. Yersinia is transmitted to patients via the oral route, via contaminated blood products, or by cutaneous inoculation. Patients developing iron overload because of multiple transfusions (i.e., thalassemia patients) are at increased risk of Yersinia infections because some strains are unable to synthesize bacterial iron chelators called siderophores. They can, however, use host-chelated iron stores or the drug deferoxamine (a siderophore produced by Streptomyces pilosus). Yersinia is associated with reactive arthritis following an infection by an enteropathogenic organism. Most patients who develop arthritis express HLA-B27.
A history of asthma (choice A) is not associated with Yersinia infections.

Deficiency in C1 esterase inhibitor activity (choice B) produces the syndrome of angioedema. This is an autosomal dominant trait associated with a deficiency of the serum inhibitor of the activated first complement component. The patients have multiple episodes of edema, affecting skin and mucosal surfaces such as the larynx and the GI tract.

Leukopenia (choice D) is not associated with the clinical scenario in the question. Normal-to-elevated leukocyte counts are the rule in Yersinia infection.

Serological positivity for toxoplasmosis (choice E) is not suggested because toxoplasmosis produces a different clinical picture. Toxoplasmosis can be acquired transplacentally with infected infants exhibiting a wide array of symptoms depending on when the mother was infected during gestation. Toxoplasmosis is also seen in immunocompromised patients such as those with AIDS. In this group of patients, the main organ system involved is the central nervous system.

[Asclepius1]

is the appendix located in the right lower quangrant

[calidoc99]

He he he......

[sameerabosamrah]

HLA -B27 POSITIVE

Acute mesentric lymphadenitis most propably caused by

yersenia enterocolitis

thx