Helicobacter pylori infection is probably the cause of chronic idiopathic neutropenia (CIN)-associated splenomegaly

Helicobacter pylori and extragastric diseases: A review

Helicobacter pylori (H. pylori) infection is very common and affects approximately half of the world population. It causes gastric diseases, but some authors have reported an association of H. pylori infection with other systemic manifestations beginning in 1994. The list of potential effects of H. pylori outside the stomach includes a number of extragastric manifestations and we focused on neurological, dermatological, hematologic, ocular, cardiovascular, metabolic, allergic, and hepatobiliary diseases. This review discusses these important reported manifestations that are not related to the gastrointestinal tract.

Hematologic manifestations of Helicobacter pylori infection

Helicobacter pylori (H. pylori) is the most common infection in humans, with a marked disparity between developed and developing countries. Although H. pylori infections are asymptomatic in most infected individuals, they are intimately related to malignant gastric conditions such as gastric cancer and gastric mucosa-associated lymphoid tissue (MALT) lymphoma and to benign diseases such as gastritis and duodenal and gastric peptic ulcers. Since it was learned that bacteria could colonize the gastric mucosa, there have been reports in the medical literature of over 50 extragastric manifestations involving a variety medical areas of specialization. These areas include cardiology, dermatology, endocrinology, gynecology and obstetrics, hematology, pneumology, odontology, ophthalmology, otorhinolaryngology and pediatrics, and they encompass conditions with a range of clear evidence between the H. pylori infection and development of the disease. This literature review covers extragastric manifestations of H. pylori infection in the hematology field. It focuses on conditions that are included in international consensus and management guides for H. pylori infection, specifically iron deficiency, vitamin B₁₂ (cobalamin) deficiency, immune thrombocytopenia, and MALT lymphoma. In addition, there is discussion of other conditions that are not included in international consensus and management guides on H. pylori, including auto-immune neutropenia, antiphospholipid syndrome, plasma cell dyscrasias, and other hematologic diseases.

Autoimmune neutropenia

Autoimmune neutropenia (AIN) is a rare entity caused by antibodies directed against neutrophil-specific antigens. It includes primary and secondary autoimmune neutropenia. Acute autoimmune neutropenia can be related to drug-induced mechanism or viral infections. Chronic autoimmune neutropenias occur in the context of autoimmune diseases, hematological malignancies, such as large granular lymphocyte leukemia, primary immune deficiency syndromes or solid tumors. The therapeutic management depends on the etiology. Granulocyte growth factor is the main therapeutic option, raising the question of their long-term utilization safety. Corticosteroids or immunosuppressive therapy are indicated in infection-related AIN or in case of symptomatic autoimmune disease or LGL leukemia.

The role of Helicobacter pylori infection in hematological disorders

Helicobacter pylori (H. pylori) is a Gram-negative spiral bacterium, classified as a carcinogen of class I, according to the World Health Organization (WHO). The infection is a major cause of gastritis, gastric and duodenal ulcer disease and increases the risk of gastric cancer. It has been implicated in the pathogenesis of several gastrointestinal, systemic or hematological diseases. The present review aims in deciphering the role of the bacterium in hematological disorders, increasing the awareness of gastroenterologists, hematologists and internal medicine practitioners, regarding the bacterium-associated hematological diseases. The efficacy of H. pylori eradication in increasing the platelet count in adult patients with primary immune thrombocytopenia (ITP) has been confirmed, linking the infection with the disease. Moreover, as the bacterium causes iron deficiency anemia (IDA) by several mechanisms, recent guidelines indicate H. pylori infection (Hp-I) to be sought in IDA patients if histology is negative and to be eradicated if present. Furthermore, it has been widely recognized that anti-H. pylori treatment causes regression of the low-grade B-cell gastric MALT lymphomas. Despite the well established associations of Hp-I with the aforementioned hematological disorders, we highlight the possible role of the infection to other hematological diseases or conditions such as non-Hodgkin lymphomas of the stomach, monoclonal gammopathy of undetermined significance, megaloblastic anemia and myelodysplastic syndromes. We finally underline the elevated risk of childhood leukemia and of hemorrhage in patients with coagulation disorders, due to the infection.

Association between helicobacter pylori infection and chronic idiopathic neutropenia

The possible association between Helicobacter pylori (H. pylori) infection and chronic idiopathic neutropenia (CIN) was investigated. A total of 78 subjects with CIN were recruited in this case-control study. As a control group, 40 subjects without CIN were selected for comparison with the case group. All participants were evaluated for the prevalence of H. pylori infection by 14C-urea breath test. The corrected splenic index (CSI) was calculated, and serum IL-6, IL-8, IL-10 and HsCRP levels were measured. The differences in CSI, serum IL-6, IL-8, IL-10 and HsCRP levels were compared between CIN patients and controls, as well as between subjects with and without H. pylori infection. The positive rate of H. pylori was 87.18% in CIN group and 52.50% in control group, showing a significant difference (Fisher's exact, P=0.000). CSI values, and serum IL-6 and HsCRP levels in H. pylori positive-CIN patients were significantly higher than those in negative subjects (Mann-whitney U-test, P=0.016, P=0.001 and P=0.000 respectively), while IL-10 level declined significantly in H. pylori negative-CIN patients (Mann-whitney U-test, P=0.000). In control group, serum IL-6 and HsCRP levels in H. pylori positive individuals were also increased significantly (Mann-whitney U-test, P=0.000), while IL-10 level declined (Mann-whitney U-test, P=0.018). Multivariate regression analysis revealed that H. pylori infection and IL-10 were significant risk factors for CIN with odds ratio (OR): 3.09, 95.0% CI: 1.22-6.93; P=0.019, and OR: 0.17, 95.0% CI: 0.05-0.94; P=0.021, respectively. This prospective study confirmed the existence of an association between H. pylori infection and CIN, suggesting the screening for H. pylori infection and eradicating bacterium in positive cases seem appropriate and beneficial for those patients with CIN diagnosis.

Association between Helicobacter pylori and liver-to-spleen ratio: a randomized-controlled single-blind study

BACKGROUND AND AIM

Helicobacter pylori infection is reported to be associated with some extragastrointestinal manifestations, such as hematological diseases (thrombocytopenia, anemia), obesity, and fatty liver disease. The length or the volume ratio of liver to spleen was suggested to be changed in some hematological and hepatobiliary disorders. We hypothesized that the liver-to-spleen ratio may be affected in H. pylori-positive patients. In this respect, we aimed to evaluate the effect of H. pylori infection on the liver-to-spleen ratio and platelet indices.

METHOD

A total of 174 patients with functional dyspepsia were included in the study. Patients were divided into group 1 (H. pylori-positive gastritis) (n=95) and group 2 (H. pylori negative, control group) (n=79). Liver, spleen length measurement, and liver steatosis scores were performed by ultrasonography by the same physicians who were blinded to the H. pylori results. Blood count values including the platelet count and the mean platelet volume (MPV) were compared between the two groups. BMI was also evaluated as a potential confounding factor for fatty liver.

RESULTS

The liver-to-spleen ratio, platelet-to-spleen ratio, MPV-to-spleen ratio, and the MPV-to-liver ratio were significantly lower in the H. pylori-positive group compared with the H. pylori-negative group (P<0.001, <0.001, <0.001, and 0.038, respectively). Fatty liver was significantly more frequent in H. pylori-positive patients.

CONCLUSION

Liver-to-spleen ratio and the MPV-to-spleen ratio are important indices in the pathogenesis of H. pylori-linked liver and spleen manifestations, and thrombocytopenia.

The clinical significance of non-malignant neutropenia in hospitalized children

Neutropenia in non-cancer patients is often discovered in the course of an evaluation for acute infection, and it is usually secondary to the infection itself rather than a predisposing factor of the infection. Although it is not a common finding in hospitalized pediatric patients, it causes a great concern to the treating physicians. The aim of this study was to determine the incidence, the etiology, and the clinical significance of neutropenia in previously healthy children admitted in a general pediatric ward. One thousand five hundred and forty-eight patients admitted during a period of 18 months were included in the study. The clinical characteristics, the complete blood count, and the sedimentation rate were recorded. A total of 143 (9.2%) pediatric patients were identified as neutropenic, with mean absolute neutrophilic count of 0.960 x 10(9)/l (SD 0.341 x 10(9)/l) and ranged from 0.200 to 1.499 x 10(9)/l. The neutropenic patients had lower hemoglobin of 11.2 mg/dl and ranged from 6.2 to 17.2 mg/dl compared to hemoglobin of 11.5 mg/dl, which ranged from 5.2 to 18.0 mg/dl of the individuals with normal neutrophils, p < 0.0001 and lower mean platelet count of 294 x 10(9)/l, which ranged from 122 to 929 x 10(9)/l compared to platelet count of 381 x 10(9)/l, which ranged from 90-165 x 10(9)/l of the individuals without neutropenia, p < 0.001. Additionally, those patients were significantly younger than the non-neutropenic ones. Infection was the most common cause of neutropenia, although none of them developed septicemia. The neutrophil count normalized in most of the patients before discharge. However, 12 (8.3%) of neutropenic patients were discharged with persistent findings. Two of those were finally diagnosed with autoimmune neutropenia. In conclusion, the acquired neutropenia in hospitalized patients without malignancy is mild to moderate. It has no influence on the clinical outcome. Importantly, it has short duration, and it is usually resolved before patient's discharge.

Neutropenia: Etiology and Pathogenesis

Neutropenia is defined as an absolute neutrophil count <1500 cells/mm(3) and can be graded as mild (1000-1500 cells/mm(3)), moderate (500-1000 cells/mm(3)), or severe (<500 cells/mm(3)). Neutropenia can develop as a result of > or =1 pathologic mechanism, including decreased bone marrow production, the sequestering of neutrophils, and increased destruction of neutrophils in the peripheral blood. The clinical result is increased risk for infection. This risk is directly proportional to the severity and duration of neutropenia. Neutropenia is classified according to the etiology as congenital or acquired, with the latter further defined according to the etiology or pathology. Febrile neutropenia is associated with substantial morbidity and even mortality.