Refine Search

New Search

Advanced search

Results: 2

(searched for: Relevance-between-Helicobacter-Pylori-Infection-and-Immune-Thrombocytopenia)
Page of 1
Articles per Page
by
Show export options
  Select all
Rania Abd El-Hamid El-Kady, Mona Mohammed Thaalab
International Journal of Hematology and Therapy, Volume 3, pp 1-6; doi:10.15436/2381-1404.17.018

Sciprofile linkNaglaa Abdallah, Hk Abdel Aziz, Na Hamed, M Gamal
Journal of Venomous Animals and Toxins including Tropical Diseases, Volume 16, pp 456-461; doi:10.1590/s1678-91992010000300012

Abstract: Hepatitis C virus (HCV) patients commonly have low platelet counts; however, the exact role of HCV
infection
in
thrombocytopenia
is unknown. This work aimed to study the serum levels of interleukins (IL) 10
and
12 in patients with mild
and
moderate
thrombocytopenia
associated with chronic hepatitis C
infection
. Our study included 15 patients with chronic HCV
infection
and
newly diagnosed isolated autoimmune
thrombocytopenia
(Group I)
and
15 patients with chronic HCV
infection
and
normal platelet count as controls (Group II). All patients were examined for personal history
and
clinical aspects, complete blood count, bone marrow aspiration, liver function tests, HCV antibody assay by ELISA
and
polymerase chain reaction (PCR), abdominal ultrasound,
Helicobacter
pylori
stool antigen test, evaluation of serum levels of IL-10, IL-12
and
platelet specific antibodies. Our results revealed that eight patients from Group l had mild
thrombocytopenia
and
seven patients had moderate
thrombocytopenia
. Serum IL-10 level was significantly elevated (t = 9.301, p < 0.001) while serum IL-12 showed a significant decrease (t = 6.502, p < 0.001) in Group I compared to the control group. No correlation was detected
between
platelet counts
and
the serum levels of either IL-10 [r = 0.454, p = 0.089 (Group I), r = 0.038, p = 0.89 (Group II)] or IL-12 [r = 0.497, p = 0.06 (Group I), r = 0.499, p = 0.058 (Group II)]. However, in Group I, a significant correlation was present only
between
moderate
thrombocytopenia
and
serum levels of either IL-10 (r = 0.794, p = 0.033) or IL-12 (r = 0.967, p = 0.001), while no correlation was detected
between
these interleukin parameters
and
mild
thrombocytopenia
(r = 0.311
and
p = 0.453 for IL-10
and
r = –0.08
and
p = 0.851 for IL-12). Based on our data, we may conclude that interleukins 10
and
12 are involved in low platelet levels. Key words: interleukin-10, interleukin-12,
thrombocytopenia
, hepatitis C activity. INTRODUCTION
Thrombocytopenia
is a common complication in patients with chronic liver disease. A platelet count less than 150.000/ µ L has been observed in up to 76% of patients. Moderate
thrombocytopenia
(platelet count ranging from 50,000 to 75,000/ µ L) occurs in approximately 13% of patients with cirrhosis (1).
Infection
with hepatitis C virus (HCV) is a major cause of chronic liver diseases. HCV antibody-positive individuals are 2.6 times more likely to have a low platelet count than those who are HCV-antibody negative (2). In untreated hepatitis C patients, both prevalence
and
severity of
thrombocytopenia
increase in parallel with the extent of the disease, usually becoming clinically
relevant
when patients develop extensive fibrosis
and
/or cirrhosis (3). The pathophysiology of
thrombocytopenia
in patients with chronic liver disease resulting from HCV
infection
is complex
and
involves several complementary mechanisms that may act in concert. Pathogenetic mechanisms comprise hypersplenism secondary to portal hypertension, bone marrow suppression resulting from either HCV itself or interferon treatment, aberrations of the
immune
system provoking the formation of antiplatelet antibodies
and
/or
immune
complexes that bind to platelets
and
facilitate their premature clearance, cross-reactivity of antiplatelet glycoprotein antibodies
and
viral antigens (antigenic mimicry) (3, 4). Development of immunologically-mediated extrahepatic manifestations including mixed cryoglobulinemia with or without associated joint, renal or cutaneous involvement
and
thrombopoietin deficiency secondary to liver dysfunction constitute another postulated mechanisms (3).
Thrombocytopenia
can potentially postpone or interfere with diagnostic
and
therapeutic procedures including liver biopsy, antiviral therapy,
and
medically indicated or elective surgery (1). In the present study, we evaluated the levels of interleukins 10
and
12 in patients presenting different degrees of autoimmune
thrombocytopenia
associated with chronic hepatitis C
infection
. PATIENTS
AND
METHODS The present study included 15 patients with chronic hepatitis C virus
infection
associated with newly diagnosed isolated autoimmune
thrombocytopenia
(Group I)
and
15 patients with chronic hepatitis C
and
normal platelet count as the control group (Group II). The two groups were matched for age
and
sex. All patients had liver cirrhosis Child class A. Patients with evidence of hypersplenism, previous recent therapy with interferon or ribavirin, positive serology for HBV, HIV or positive H.
pylori
antigen in the stool were excluded from the study. All patients were subjected to: Statistical analysis The SPSS package, version 9.0 for Windows ® (Microsoft, USA), was used for statistical analysis of data. Student's t-test was employed to compare means of age, hematological
and
chemical parameters
between
patients
and
the control group. The χ 2 -test was utilized for comparison of sex distribution into Group I or Group II. Associations
between
the different studied variables were evaluated with Pearson's correlation (r); p < 0.05 was considered significant. Data are shown as mean ± standard deviation (SD). RESULTS The clinical
and
laboratory data of the studied groups are shown, respectively, in Tables 1
and
2 . Clinically evident bleeding was present in nine out of 15 (60%) patients in the form of recurrent epistaxis
and
gingival bleeding. Mild
thrombocytopenia
(platelet count > 75,000/ µ L
and
< 150,000/ µ L) was present in eight out of 15 (53%) patients whereas moderate
thrombocytopenia
(platelet count
between
50,000/ µ L
and
75,000/ µ L) was found in seven out of 15 (47%) individuals (1). Table 3 presents the correlation
between
platelet counts
and
serum levels of interleukins 10
and
12 in HCV positive group associated with moderate
thrombocytopenia
. No correlation was detected
between
platelet count
and
the serum levels of either IL-10 (r = –0.038, p = 0.89 for controls; r = 0.454, p = 0.089 for HCV positive group associated with
thrombocytopenia
) or IL-12 (r 0.499, p = 0.058 for controls, r = 0.497; p = 0.06 for HCV positive group associated with
thrombocytopenia
). However, moderate
thrombocytopenia
was significantly correlated with serum levels of both IL-10 (r = 0.794, p = 0.033)
and
IL-12 (r = 0.967, p = 0.001); although such correlation was not detected in mild
thrombocytopenia
(r = 0.311, p = 0.851 for IL-10
and
r = –0.08, p = 0.453 for IL-12). The respective mean values of interleukins 10
and
12 in HCV positive cirrhotic patients associated with moderate
thrombocytopenia
were: 15.86 ± 3.89 pg/mL
and
4.57 ± 4.45 pg/mL. DISCUSSION HCV
infection
may be associated with significant
thrombocytopenia
and
appears to be a distinct clinical entity (10). Moderate
thrombocytopenia
was present in seven out of 15 (47%) patients while mild
thrombocytopenia
was detectable in eight out of 15 (53%). In a previous study of HCV-thrombocytopenic patients, 4% had severe
thrombocytopenia
( < 10 x 10 9 /L) while 74% had a maximum platelet count of 50 x 10 9 /L (10). The mean age of our patients was 58 years in Group l
and
55 years in Group II with no statistically significant difference
between
the two groups as to age or sex. The prevalence of
thrombocytopenia
in older persons with HCV
infection
was 6.6 times greater than that among the elderly without HCV
infection
and
equally distributed
between
genders. Anti-HCV-positive older individuals were three times more likely than persons in other age groups to have
thrombocytopenia
. This might be related to poorly compensated platelet production, especially in individuals with severe liver disease (11). In our study bleeding was clinically evident in nine out of 15 (60%) studied thrombocytopenic patients in the form of recurrent epistaxis
and
gum bleeding. The majority of older individuals with anti-HCV
and
thrombocytopenia
are asymptomatic, but major bleeding was more frequent (10). Similarly, in the current work, all patients had liver cirrhosis Child class A. HCV-
infection
-associated
thrombocytopenia
was correlated with hepatocellular damage
and
hepatic fibrosis (11). The prevalence of
thrombocytopenia
increased markedly with liver disease severity among patients with HCV
infection
; the prevalence was about nine times higher among subjects with chronic hepatitis, cirrhosis, or hepatoma than among those with a normal or fatty liver (11). The exact role of HCV
infection
in the occurrence of
thrombocytopenia
is unknown. An impaired thrombopoietin (TPO) production did not explain the development of
thrombocytopenia
in HCV
infection
. It was suggested that TPO production is maintained at certain levels until profound impairment of hepatic function has developed, when other organs may compensate the decrease in TPO production by the liver (2). Therefore, other mechanisms must be involved. Dysregulation of T-helper (Th1/Th2) cytokine production may play an important role in immunopathogenesis of chronic hepatitis C (CHC) (12). In CHC patients, interferon- γ (IFN- γ )
and
IL-12 levels drop as a result of the enhanced IL-10 production, which serves as a possible down-regulator of IFN- γ (13). Further research on the role of these cytokines in HCV
infection
associated with
thrombocytopenia
may clarify additional functions of these cytokines. IL-10 is an important immunoregulatory cytokine
and
its main biological functions seem to be the limitation
and
termination of inflammatory responses
and
the regulation of differentiation
and
proliferation of T cells, B cells, natural killer cells, antigen-presenting cells, mast cells
and
granulocytes. Moreover, IL-10 promotes the development of a type 2 cytokine pattern by inhibiting IFN- γ production (14). The present study revealed statistically significant elevation in serum IL-10 levels in Group I (HCV associated with
thrombocytopenia
) when compared with Group II. HCV-specific IL-10
Page of 1
Articles per Page
by
Show export options
  Select all