helicobacter pylori infection is associated with advanced colorectal neoplasia

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Scandinavian Journal of Gastroenterology. 2014; 49: 516517 LETTER TO THE EDITOR Helicobacter pylori infection is associated with advanced colorectal neoplasia HAIM SHMUELY, EHUD MELZER, MICHAL BRAVERMAN, NOAM DOMNITZ & JACOB YAHAV Kaplan Medical Center, Rehovoth, Israel To the Editor, Kountouras et al. [1] in their letter commenting on our study [2] stated that only current Helicobacter pylori infection (Hp-I) reduces humoral and cellular immune responses inducing or perpetuating chronic inammatory processes in the gastrointestinal tract with potential oncogenic sequelae. Most malignan- cies, including colorectal carcinoma (CRC), occur at the chronic inammation sites and infection. In our study [2], we used two serology tests. ELISA, validated in our laboratory, involving patients who had undergone an endoscopy at our hospital, yielded a sensitivity of 94% and specicity of 90%. Positive and negative predictive values of 100% and 90%, respectively, were observed. We also tested for IgG antibodies against CagA protein with immuno- blot staining using a Western blot kit (Helicoblot 2.0; Genelabs Diagnostic, Singapore). CRC is a slow-growing cancer and it takes up to 18 years for a dysplastic cell to transform to cancer [3], and Hp-I initiates the process. The low rates of natural acquisition and elimination of Hp in adults [4] suggest that there is almost no self- elimination of the bacteria that persists throughout life; thus, serology may remain positive even after curing the infection [5]. In patients treated with antisecretory drugs, H. pylori antibodies persist. Pos- itive antibody levels were found in 86% of patients with chronic atrophic gastritis; however, positive histology was only apparent in 33% of the subjects and in patients after gastrectomy [6]. Regarding Kountourasletter [1], the authors base their results on only 50 CRC patients and 25 patients with colorectal adenomas (CRAs) and only 10 controls. The number of controls is unusu- ally low and do not represent a comparable group. The authors neither specify gender and age of patients and controls nor their socioeconomic status. As to the small number of cases, the presence of Hp-I in the CRA (68%) and CRC (84%) groups has no statistical signicance in univariate analysis, especially without multivariate analysis for confoun- ders. Only 8 out of 50 CRC and 8 out of 25 patients with CRAs were Hp negative, rendering it very dif- cult to reach any conclusions, especially regarding Hp eradication. The results presented by Kountouras et al. [1] indicate that Hp-I impacts colorectal oncogenesis, thus supporting our results and conclusion. Declaration of interest: The authors report no conicts of interest. The authors alone are responsible for the content and writing of the paper. References [1] Kountouras J, Kapetanakis N, Zavos C, Polyzos SA, Kouklakis G, Venizelos I, et al. Active Helicobacter pylori infection is associated with colorectal mucosa - adenomatous polyp - early and advanced adenocarcinoma sequence. Scand J Gastroenterol 2013;Epub ahead of print. [2] Shmuely H, Melzer E, Braverman M, Domniz N, Yahav J. Helicobacter pylori infection is associated with advanced Correspondence: Haim Shmuely MD, Kaplan Medical Center, Rehovoth, Israel. E-mail: [email protected] (Received 22 December 2013; accepted 24 December 2013) ISSN 0036-5521 print/ISSN 1502-7708 online Ó 2014 Informa Healthcare DOI: 10.3109/00365521.2013.879336 Scand J Gastroenterol Downloaded from informahealthcare.com by Ondokuz Mayis Univ. on 11/06/14 For personal use only.

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Page 1: Helicobacter pylori               infection is associated with advanced colorectal neoplasia

Scandinavian Journal of Gastroenterology. 2014; 49: 516–517

LETTER TO THE EDITOR

Helicobacter pylori infection is associated with advanced colorectalneoplasia

HAIM SHMUELY, EHUD MELZER, MICHAL BRAVERMAN, NOAM DOMNITZ &JACOB YAHAV

Kaplan Medical Center, Rehovoth, Israel

To the Editor,Kountouras et al. [1] in their letter commenting on

our study [2] stated that only current Helicobacterpylori infection (Hp-I) reduces humoral and cellularimmune responses inducing or perpetuating chronicinflammatory processes in the gastrointestinal tractwith potential oncogenic sequelae. Most malignan-cies, including colorectal carcinoma (CRC), occur atthe chronic inflammation sites and infection.In our study [2], we used two serology tests.

ELISA, validated in our laboratory, involving patientswho had undergone an endoscopy at our hospital,yielded a sensitivity of 94% and specificity of 90%.Positive and negative predictive values of 100% and90%, respectively, were observed. We also tested forIgG antibodies against CagA protein with immuno-blot staining using a Western blot kit (Helicoblot 2.0;Genelabs Diagnostic, Singapore).CRC is a slow-growing cancer and it takes up to

18 years for a dysplastic cell to transform tocancer [3], and Hp-I initiates the process. The lowrates of natural acquisition and elimination of Hp inadults [4] suggest that there is almost no self-elimination of the bacteria that persists throughoutlife; thus, serology may remain positive even aftercuring the infection [5]. In patients treated withantisecretory drugs, H. pylori antibodies persist. Pos-itive antibody levels were found in 86% of patientswith chronic atrophic gastritis; however, positivehistology was only apparent in 33% of the subjectsand in patients after gastrectomy [6].

Regarding Kountouras’ letter [1], the authorsbase their results on only 50 CRC patients and25 patients with colorectal adenomas (CRAs) andonly 10 controls. The number of controls is unusu-ally low and do not represent a comparable group.The authors neither specify gender and age ofpatients and controls nor their socioeconomicstatus. As to the small number of cases, the presenceof Hp-I in the CRA (68%) and CRC (84%) groupshas no statistical significance in univariate analysis,especially without multivariate analysis for confoun-ders. Only 8 out of 50 CRC and 8 out of 25 patientswith CRAs were Hp negative, rendering it very dif-ficult to reach any conclusions, especially regardingHp eradication.The results presented by Kountouras et al. [1]

indicate that Hp-I impacts colorectal oncogenesis,thus supporting our results and conclusion.

Declaration of interest: The authors report noconflicts of interest. The authors alone are responsiblefor the content and writing of the paper.

References

[1] Kountouras J, Kapetanakis N, Zavos C, Polyzos SA,Kouklakis G, Venizelos I, et al. Active Helicobacter pyloriinfection is associated with colorectal mucosa - adenomatouspolyp - early and advanced adenocarcinoma sequence. Scand JGastroenterol 2013;Epub ahead of print.

[2] Shmuely H, Melzer E, Braverman M, Domniz N, Yahav J.Helicobacter pylori infection is associated with advanced

Correspondence: Haim Shmuely MD, Kaplan Medical Center, Rehovoth, Israel. E-mail: [email protected]

(Received 22 December 2013; accepted 24 December 2013)

ISSN 0036-5521 print/ISSN 1502-7708 online � 2014 Informa HealthcareDOI: 10.3109/00365521.2013.879336

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Page 2: Helicobacter pylori               infection is associated with advanced colorectal neoplasia

colorectal neoplasia. Scand J Gastroenterol 2014;49:35–42.

[3] Kozuka S, Nogaki M, Ozeki T, et al. Premalignancy ofthe mucosal polyp in the large intestine: II. Estimationof the periods required for malignant transformation ofmucosal polyps. Dis Colon Rectum 1975;18:494–500.

[4] Xia HH, Talley NJ. Natural acquisition and spontaneouselimination of Helicobacter pylori infection: clinicalimplications. Am J Gastroenterol 1997;92:1780–7.

[5] Morris AJ, Ali MR, Nicolson GI, Perez-Perez GI,Blaser MJ. Long-term follow-up of voluntary ingestionof Helicobacter pylori. Ann Intern Med 1991;114:662–3.

[6] Karnes WE, Samloff IM, Siurala M, Kekki M, Sipponen P,Kim SW, et al. Positive serum antibody and negative tissuestaining for Helicobacter pylori in subjects with chronicatrophic body gastritis. Gastroenterology 1991;101:167–74.

Letter to the Editor 517

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