[700] Eosinophilic Proctocolitis in Infants

AM O'Shea, G Mazzoleni, RH Riddell. Beaumont Hospital, Dublin, Ireland; Azienda Sanitaria dell'Alto Adige, Bolzano, Italy; Mount Sinai Hospital, Toronto, Canada

Background: Allergic/eosinophilic proctocolitis(EP) is a significant cause of proctocolitis in the early years of life. The clinical findings are often non-specific & include bloody diarrhoea. Accurate diagnosis relies on the exclusion of other causes & the appropriate response to dietary elimination of the relevant protein. Examples in neonates are thought to be related to ingested cow's milk proteins in maternal breast milk, but in older weaning infants to direct ingestion. Studies of histologic changes in EP describe increased numbers of eosinophils in the lamina propria(LP), crypts & muscularis mucosae(MM) & focality of changes. In this study we characterise the spectrum of histologic findings in EP in neonates, older infants & also those in whom cow's milk was not clearly involved in the underlying disease.
Design: 91 biopsies from 53 infants (24 females; 29 males) were retrieved from the pathology departments of two institutions and grouped as follows: Group 1: 0-7months with a diagnosis of EP; Group 2: >7 (18-59)months with a diagnosis of EP & Group 3: 2-50 months with varied non-EP aetiologies. The slides and report from each biopsy were reviewed, the site recorded and a number of parameters assessed including: Architectural distortion(AD); average eosinophil(Eos) count per hpf in the LP; Eos. distribution; Eos. in crypts, MM & surface epithelium(SE); neutrophils(N) in the LP & crypts; & chronic inflammatory cells(CI) in the LP.
Results: 54/55 biopsies were left sided/rectal in Group1; 11/19 were left sided in Group2 & 16/17 in Group3. The mean no. Eos/hpf was: Group1: 10; Group2: 13; Group3: 14. Other results are as follows:

Table 1.
Group1(n/%)Group2(n/%)Group3(n/%)
AD2(4)*5(26)*12(70)*
Focal increase in Eos. in LP48(87)*13(68)*7(41)*
Eos present in crypts41(74)11(58)12(70)
Eos present in MM (MM not included in all cases)27(69)11(92)8(73)
N present in LP6(11)*4(21)*17(100)*
N present in crypts5(9)*4(21)*17(100)*
Increase in CI in LP0(0)*4(21)*13(76)*
Eos. SE27(49)3(15)17(100)
TOTAL NO. BIOPSIES55(100)19(100)17(100)
*p<0.05; Group1 or 2 vs. Group3; Fisher's exact test


Conclusions: This study characterises the changes of EP and confirms the significance of focality of raised eosinophils in the LP. The first 2 groups are similar morphologically, but group 3 appears to be a more severe disease, but currently of uncertain aetiology.
Category: Gastrointestinal

Wednesday, March 24, 2010 9:30 AM

Poster Session V # 57, Wednesday Morning

 

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