Response to: regarding the significance of anti-COVID-IgA antibody response in COVID-19 breakthrough infection.

In response to Chen et al.'s comments on our paper regarding the significance of anti-COVID-IgA antibody response in COVID-19 breakthrough infection in vaccinated patients, we have highlighted the role and the scope of this paper in this correspondence. The role of anti-COVID-19-IgA is already known. The objective of the previous study was to see its role in breakthrough-infected patients. To analyse this effect, we recruited patients with COVID-19 infection after they were fully vaccinated and compared them with the vaccinated group who did not get the infection. Both groups were equally exposed to the virus as all of them were health care workers. We also showed that the anti-COVID-19-NP-IgA was absent in the healthy cohort of our study groups, signifying the absence of natural infection in them during this period. The article also highlights the importance of vaccinating all individuals including those who are immunosuppressed, as it prevents severe COVID-19 infection in these individuals. The physicians should be aware of the fact that immunosuppressed patients are more likely to get COVID-19 breakthrough infection. However, proper vaccination with booster doses prevents severe infection in them.

Breakthrough COVID-19 infections - Analyzing our experience.

Objective: There are many cases of post-vaccination COVID-19 globally. Also, literature on serum antibodies after vaccination is abundant. Our research focuses on breakthrough infections reported at our institution during the third wave of COVID-19. Methods: A total of 177 people recruited at the Indus Hospital Karachi between May to September 2021 with COVID-19 infection were divided into vaccinated, partially vaccinated, and unvaccinated cohorts. Furthermore, a subset of the vaccinated cohort was tested for anti-NP and anti-S antibodies. Results: There were 119 patients with breakthrough infection, however, 74% had mild symptoms. The antibodies against NP and S were found at a higher level in those who had a breakthrough infection in comparison to healthy vaccinated controls. Conclusion: Vaccination does not prevent disease but does confer some immunity causing less severe infection.

Plasmablastic Lymphoma in a Human Immunodeficiency Virus-positive Child With a Suspicion of Concomitant Primary Immunodeficiency Disorder.

Plasmablastic lymphoma (PBL) occurs in the setting of immunodeficiency, in association with human immunodeficiency virus (HIV) infection, in elderly patients, and in the posttransplantation state. It is exceptionally rare in children. PBL is an aggressive lymphoma with a poor prognosis. We present a case of pediatric PBL in an HIV-positive child with suspicion of a concomitant underlying immune deficiency state other than HIV. A 7-year-old girl presented to the pediatric emergency department with complaints of fever and painful swelling on the left side of her face for 15 days, associated with headache, snoring, and difficulty in breathing. She had a history of watery diarrhea, oral thrush, recurrent fever, and hospitalizations for skin infections since the age of 1 year. Histopathological findings were consistent with PBL. Her HIV RNA polymerase chain reaction was positive. She was offered chemotherapy based on the FAB/LMB 96 protocol. This case demonstrates an aggressive presentation of a rare entity, HIV-associated PBL, in a child, with underlying immunodeficiency and highlights the issues which caused a significant challenge in making the diagnosis. The presence of HIV infection and contradicting other immunologic investigations posed a dilemma in establishing an association of PBL in this child. The outcome of patients with this tumor is associated with high mortality.

Significance of Anti-COVID-IgA antibody response in COVID-19 breakthrough infection in vaccinated patients - a single-centered study from Pakistan.

An increasing number of breakthrough-COVID-19-vaccinated individuals are being reported across the world. Humoral immunity has a crucial role in combating infection. In this study, we aimed to assess the importance of anti-COVID-S1-IgA and anti-COVID-NP-IgA in confirmed COVID-19 after vaccination (breakthrough infection group). Blood samples were collected from the breakthrough infection group within one week of breakthrough infections (n = 34). A second sample was also collected after 4 to 8 weeks (n = 27). Blood samples of healthy individuals (n = 29) were collected 4-8 weeks after the completion of vaccination. Anti-COVID-S1-IgA and anti-COVID-NP-IgA were detected by ELISA. Statistical analysis was performed using IBM SPSS version 24. In this study, we found a higher positivity rate for anti-COVID-S1-IgA in the breakthrough infection group (70% vs. 28% in healthy individuals). Anti-COVID-NP-IgA was not found in the control group (11% in the breakthrough infection group vs. 0 in healthy individuals). In the breakthrough-infected group, the positivity rate of anti-COVID-NP-IgA decreased significantly (median titers 16.9 IU/ml decreased to 4.2 IU/ml) p = 0.001), while anti-COVID-S1-IgA increased over a period of 4-8 weeks (9.35-16.35 IU/ml). Importantly, IgA response to both COVID-19 NP and S1 antigens was not found in 13 patients at initial testing. The findings of this study show that serum IgA may have a role both in breakthrough infections and also in the prevention of severe infection. Sluggish anti-COVID-19-IgA antibody response may be responsible for the occurrence of COVID-19 infection in breakthrough infection. On the other hand, more sustained anti-COVID-19-S1-IgA over a longer period of time may have a role in preventing these patients from severe infections and hospitalization. However, a study on a larger sample size including patients with severe disease after vaccination is required to prove this hypothesis. To the best of our knowledge, this is the first study reporting the importance of serum IgA in breakthrough-infected patients from our region.

Rare and heterogeneous manifestations of leucocyte adhesion deficiency type 1: report of two cases with diagnostic dilemmas and novel ITGB2 mutation.

BACKGROUND: Primary immunodeficiency disorders (PID) are rare disorders with heterogeneous manifestations, overlapping with other diseases such as autoimmunity, malignancy, and infections. This makes the diagnosis very challenging and delays management. Leucocyte adhesion defects (LAD) are a group of PIDs in which patients lack adhesion molecules on leukocytes needed for their emigration through blood vessels to the site of infection. Patients with LAD can present with diverse clinical features including severe and life-threatening infections, early in life, and the absence of pus formation around infection or inflammation. There is often delayed umbilical cord separation, omphalitis, late wound healing, and a high white blood cell count. If not recognized and managed early, can lead to life-threatening complications and death. CASE PRESENTATION: LAD 1 is characterized by homozygous pathogenic variants in the integrin subunit beta 2 (ITGB2) gene. We report two cases of LAD1 with unusual presentations (post-circumcision excessive bleeding and chronic inflammation of the right eye) which were confirmed by flow cytometric analysis and genetic testing. We found two disease-causing ITGB2 pathogenic variants in both cases. CONCLUSIONS: These cases highlight the importance of a multidisciplinary approach to recognizing clues in patients with uncommon manifestations of a rare disease. This approach initiates a proper diagnostic workup of primary immunodeficiency disorder leading to a better understanding of the disease, and appropriate patient counseling, and helps clinicians to be better equipped to deal with complications.

ANA-specific antibodies, ANA patterns, anti-ds-DNA results, and clinical diagnosis: a laboratory and clinical audit.

The diagnosis of systemic autoimmune diseases (SAID) is challenging, due to overlapping features with other non-immune disorders. Anti-nuclear antibodies (ANA)/anti-cellular antibodies are the sensitive screening tests but anti-double-stranded-deoxyribonucleic acid-antibody (anti-ds-DNA) and ANA-specific antibodies are specific for SAID. We aimed to look at ANA-specific antibodies in our patients and correlated them with ANA patterns, anti-ds-DNA, and clinical diagnosis for proper interpretation and better patient management cost-effectively. A retrospective data analysis of 641 patients was done (1st of February 2019 to 31st of July 2021) who were tested for ANA-specific antibodies at the Immunology Department of Indus Hospital and Health Network. ANA and anti-ds-DNA results and clinical diagnosis were also analyzed for ANA-specific antibody-positive patients. Descriptive data were presented in mean ± standard deviation and frequency percentages whereas inferential data were analyzed with a chi-square test for association between ANA-specific antibodies status, ANA, anti-ds-DNA, and clinical features. ANA-specific antibodies test revealed positivity for at least one autoantibody in 245 (38.2%) patients. Of these, ANA was tested in 206 patients reactive for ANA-specific antibodies and found positive in 195 (95%) as compared to negative (< 0.001). Speckled and homogenous were predominant ANA patterns in ANA-specific antibody-positives (56% and 42% respectively). Multiple ANA patterns were found in 18 patients most commonly with systemic lupus erythematosus (SLE) and mixed connective tissue disorder (MCTD). Anti-SSA were the most common ANA-specific antibodies (50%) and were mostly found in sera with speckled (61/97) and homogenous (38/97) patterns and associated mostly with SLE (48%) and Sjogren's syndrome (86%). Among ANA-negative patients, anti-SSA were the most common antibodies (n = 5). Anti-ds-DNA was found in 66% of SLE patients along with another ANA-specific antibody. This study showed that testing for ANA-specific antibodies cannot be gated on ANA patterns. Also, there is a redundancy of these antibodies with various clinical diagnoses. Moreover, they are useful in making a diagnosis in ANA-negative patients as well with clinical suspicion.

Association of Seroconversion Status with Outcome in Admitted Covid-19 Patients.

OBJECTIVE: To determine the association between seroconversion status and outcome in admitted COVID-19 patients and compare inflammatory markers amongst them. STUDY DESIGN: Single cohort observational study. PLACE AND DURATION OF STUDY: Indus Hospital and Health Network between 10th May and 10th July 2020. METHODOLOGY: All admitted patients were tested serially for anti-COVID-IgM and IgG until their sera showed positive results. This was continued until their expiry or discharge. Those patients who remained negative for both anti-COVID-19-IgG and IgM were labeled as non-seroconverts. Demographics, comorbidities, inflammatory marker levels and outcome (alive/expired) were compared between seroconverts and non-seroconverts. RESULTS: In 224 admitted patients, the median seroconversion time of IgM and IgG was six and seven days in survivors and non-survivors respectively. Expired patients displayed higher levels of procalcitonin (maximum), C-reactive protein, and Interleukin-6 (baseline and maximum). Of 34 non-seroconverts, 17 (50%) expired. Non-seroconverts significantly failed to develop fever and had lower levels of ferritin, CRP, and LDH. CONCLUSION: Non-seroconversion in hospitalised COVID-19 infected patients indicated muted immune and acute phase response and was associated with poor outcomes. Hence these patients need to be carefully evaluated and managed. KEY WORDS: Antibody response, Corticosteroids, Immunosuppression, SARS-Cov-2, Seroconversion.

Neutralizing Antibody Response to BBIBP-CorV in Comparison with COVID-19 Recovered, Unvaccinated Individuals in a Sample of the Pakistani Population.

Fifty five percent of the Pakistani population is still unvaccinated with the two-dose protocol of COVID-19 vaccines. This study was undertaken to determine the seroconversion rate and antibody titers following the two-dose BBIBP-CorV protocol, and to compare these variables in unvaccinated, COVID-19 recovered individuals (total n = 180) at Indus Hospital and Health Network, Karachi. Pseudotyped lentivirus antibody neutralization assays and SARS-CoV-2 IgG Quant II (Abbott) immunoassays were performed 4-8 weeks following the second dose of the BBIBP-CorV or PCR positivity/onset of symptoms of COVID-19. Seroconversion rate, using neutralization assays, in vaccinated individuals was lower (78%) than that in unvaccinated, COVID-19-recovered individuals with moderate to severe infection (97%). Prior PCR positivity increased serocoversion rate to 98% in vaccinated individuals. Immunoassays did not, however, reveal significant inter-group differences in seroconversion rates (≥95% in all groups). Log10 mean antibody neutralizing titers following the two-dose BBIBP-CorV protocol (IC50 = 2.21) were found to be significantly less than those succeeding moderate to severe COVID-19 (IC50 = 2.94). Prior SARS-CoV-2 positivity significantly increased post-vaccination antibody titers (IC50 = 2.82). Similar inter-group titer differences were obtained using the immunoassay. BBIBP-CorV post-vaccination titers may, thus, be lower than those following natural, moderate to severe infection, while prior SARS-CoV-2 exposure increases these titers to more closely approximate the latter.

Sensitivity and Specificity of Anti-SARS-CoV-2 Detection Kits - Comparison and Agreement between Fifteen Different Assays.

Accurate and rapid diagnosis of coronavirus disease 2019 (COVID-19) is critical for proper care and identification of affected individuals. This led to early availability of many serological assays in the market, but with limited validation. In this study, we aimed to validate the serological assays based on different techniques. We evaluated 15 different assays based on four immunoassay techniques in 235 patients. The most sensitive kits employed were as follows: immunochromatography (Zybio severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2] IgM/IgG Antibody Assay Kit - 83%), ELISA (Aeskulisa SARS-CoV-2 NP IgG -88.1%), chemiluminescence (Alinity SARS-CoV-2 IgG - 82.2%), and immunofluorescence (Lifotronic FA160 (Shenzhen SARS-CoV-2 Assay Kit [IgG]) - 88.9%). The kits by Uniper (Singuway Biotec COVID-19 IgM/IgG Presumptive Kit), Genrui 2019-nCoV IgM/IgG Test Kit, Wondfu SARS-CoV-2 Antibody Test, and Aeskulisa SARS-CoV-2 NP IgG exhibited 100% specificity, whereas IgG assay using Lifotronic FA160 (Shenzhen SARS-CoV-2 Assay Kit) exhibited the lowest specificity at 58%. Maximum agreement was observed between Aeskulisa SARS-CoV-2 NP IgG and Alinity SARS-CoV-2 IgG at 94%. Serological tests are practical alternatives, but their reliability depends on critical validation. The COVID-19 pandemic warranted investment in healthcare research at both the national and international levels.

Multiple Autoimmune Syndrome: An Unusual Combination of Autoimmune Disorders.

BACKGROUND: Autoimmune diseases are multifactorial with environmental and heritable factors. Autoimmunity reflects an altered immune status, therefore the presence of more than one disorder is not uncommon. The coexistence of three or more autoimmune diseases in a patient constitutes multiple autoimmune syndrome (MAS). This is an interesting case of a middle-aged female who had celiac disease, primary biliary cholangitis, autoimmune hepatitis and evolving CREST (Calcinosis, Rhaynaud's phenomenon, Esophageal dysmotility, Sclerodactyly and Telangiectasia) syndrome. CASE REPORT: Fifty years old female patient presented with generalized fatigue, fever, weight loss, vertigo and constipation. She was a diagnosed case of celiac disease, and responded well to glutenfree diet. Family history was unremarkable for any autoimmune disorder. Laboratory workup showed normal complete blood counts, markedly elevated transaminases and alkaline phosphates. Her antinuclear antibodies (ANA) test was strongly positive (>1:320) and showed an anti-centromere pattern. Anti-extractable nuclear antibody(ENA) assay showed anti-mitochondrial and anti- CENP B antibodies. Liver biopsy revealed overlap syndrome (primary biliary cholangitis and autoimmune hepatitis). This patient had celiac disease, primary biliary cholangitis and autoimmune hepatitis. Extensive immunological workup unexpectedly revealed the presence of anti-centromere protein B (anti-CENP B) antibodies which are strongly associated with CREST syndrome. Clinical re-evaluation of the patient gave clues of the evolving CREST syndrome. This case report highlights the importance of adequate immunological investigations in conjunction with clinical information for adequate patient management to achieve favorable consequences in the future. CONCLUSION: Patients suffering from an autoimmune disease need special attention as multiple immune- mediated disorders may be present simultaneously or sequentially during the course of the disease process. MAS patients are at a higher risk of acquiring infections and tumor development due to prolonged use of immunosuppressants. These patients need close surveillance for the development of another autoimmune disease, so as to control the current disease and to prevent future complications. This case report emphasizes the importance of a multidisciplinary team approach including an immunologist who may facilitate a better understanding of disorders related to the breakdown of immune tolerance.

Clinical Significance of Anti-Ribosomal P Protein Antibodies in Patients with Lupus Nephritis.

BACKGROUND: Systemic Lupus Erythematosus (SLE) is a chronic inflammatory disorder affecting multiple systems of the body. Clinical features show wide variations in patients with the different ethnic background. Renal involvement is a predictor of poor prognosis. Immunological workup is an integral part of SLE diagnostic criteria. Anti-ribosomal P Protein (anti-P) antibodies are highly specific for SLE. They may be present in Antinuclear Antibodies (ANA) negative SLE patients. Their role in Lupus Nephritis (LN) is under debate, some researchers found them associated with poor prognosis whereas others found favorable effect of these antibodies on renal disease. OBJECTIVE: In this study, we investigated frequency of anti-P antibodies and the effect of these antibodies on renal functions in the LN patients. METHODS: A total of 133 SLE patients were enrolled in this study. All patients had ANA in their sera. Anti-P antibodies along with other autoantibodies against extractable nuclear antigens (anti-Sm, anti- SS-A, anti-SS-B, anti-histones and anti-RNP) were detected by Immunoblot assay. Anti-dsDNA antibodies were detected by indirect Immunofluorescence Assay (IFA). RESULTS: We found anti-P antibodies in 10.5% LN patients. Interestingly their presence in association with anti-dsDNA was associated with improved renal functions in comparison to those who had antidsDNA antibodies in isolation (serum creatinine: 1.3 ± 0.8 mg/dl vs. 3.0 ± 3.0; P= 0.091). CONCLUSION: Anti-dsDNA antibodies are directly involved in renal pathology in SLE patients. As these antibodies are nephrotoxic, concomitant occurrence of anti-P antibodies seems to offer a shielding effect on renal functions, which was evident by normal serum creatinine levels. Therefore, anti-P antibodies may be considered as a good prognostic marker in these patients.

Autoimmune pancreatitis with extraocular muscles involvement.

Autoimmune pancreatitis is characterised by diffuse enlargement of pancreas, narrowing of pancreatic duct, lymphoplasmacytic infiltrations and fibrosis. The disease is responsive to corticosteroid. We report the case of a 32-year-old male who presented with unilateral exophthalmos and obstructive jaundice secondary to pancreatic head mass and biliary tract stricture. Serum immunoglobulin G level was raised with a very high immunoglobulin G4 subclass. Ophthalmological imaging revealed unilateral thickening of extraocular muscles. The patient responded well to corticosteroid with resolution of biliary strictures, pancreatic head mass and exophthalmos.

Vasculitis with renal involvement in essential mixed cryoglobulinemia: Case report and mini-review.

The discovery of a strong association between hepatitis C virus (HCV) infection and mixed cryoglobulinemia (MC) has led to an increasingly rare diagnosis of idiopathic essential MC (EMC). The incidence of EMC is high in regions where there is a comparatively low HCV infection burden and low in areas of high infection prevalence, including HCV. The diagnosis of EMC requires an extensive laboratory investigation to exclude all possible causes of cryoglobulin formation. In addition, although cryoglobulin testing is simple, improper testing conditions will result in false negative results. Here, we present a 46-year-old female patient with a case of EMC with dermatological and renal manifestations, highlighting the importance of extensive investigation to reach a proper diagnosis. We review the need for appropriate laboratory testing, which is often neglected in clinical practice and which can result in false negative results. This review also emphasizes the significance of an extended testing repertoire necessary for better patient management. Despite a strong association of MC with HCV infection and other causes that lead to cryoglobulin formation, EMC remains a separate entity. Correct diagnosis requires proper temperature regulation during sample handling, as well as characterization and quantification of the cryoprecipitate. Inclusion of rheumatoid factor activity and complement levels in the cryoglobulin test-panel promotes better patient management and monitoring. Consensus guidelines should be developed and implemented for cryoglobulin detection and the diagnosis of cryoglobulinemic syndrome, which will reduce variability in inter-laboratory reporting.

Clinical Profile and HLA Typing of Autoimmune Hepatitis From Pakistan.

BACKGROUND: Human leukocyte antigen (HLA) typing in autoimmune hepatitis (AIH) has been investigated in different populations and ethnic groups, but no such data is available from Pakistan. OBJECTIVES: The aim of this study was to evaluate the clinical profile of autoimmune hepatitis (AIH), and determine the associated antigens and alleles by performing HLA typing. PATIENTS AND METHODS: A total of 58 patients, diagnosed and treated as AIH in the last 10 years were reviewed. Diagnosis was based on International AIH Group criteria. Forty one patients underwent liver biopsy. HLA typing was performed in 44 patients and 912 controls by serological method for HLA A and B, and by PCR technique using sequence specific primers for DR alleles. RESULTS: Of 58 cases, 35 were females (60.3%). The median age was 14.5 (range 4-70 years), and AIH score was 14 (10-22). Thirty-six (62.0%) patients had type 1 AIH, 10 (17.2%) type 2, and the remaining 12 were seronegative with biopsy proven AIH. Forty-nine patients (84.4%) had cirrhosis. Twenty-four (41.4%) patients had ascites at the time of presentation. Among 41 patients who underwent liver biopsy, thirty-two had advance stages III and IV disease, and twenty had severe grade of inflammation. Fifteen patients had other associated autoimmune diseases and one developed hepatocellular carcinoma. HLA A2 (P = 0.036), HLA A9 (23) (P = 0.018), HLA A10 (25) (P = 0.000), HLA A19 (33) (P = 0.000), HLA B15 (63) (P = 0.007), HLA B40 (61) ( P = 0.002), HLA DR6 (P = 0.001) with its subtypes HLA-DRB1*13 (P = 0.032) and HLA-DRB1*14 (p = 0.017) were more prevalent in AIH with statistical significance than controls. CONCLUSIONS: AIH in our region presents with advanced disease affecting predominantly children and adolescents. There is a genetic association of HLA DR6 along with other alleles and antigens in our patients with AIH.

Job's syndrome with an atypical presentation.

Hyper Immunoglobulin E syndrome also called Job's or Buckley Syndrome is a rare primary immunodeficiency disease characterized by elevated serum IgE levels (> 2000 IU/ml), recurrent infections and eosinophilia. Other features include coarse facies and non-immunologic abnormalities of the dentition, bones, vasculature and connective tissues. We are reporting a case of a twenty four years old male with coarse facies who presented with severe pallor and upper gastrointestinal bleeding. Investigations revealed markedly elevated serum IgE levels (11,800 IU/ml), severe anaemia, esophageoduodenal erosions, Helicobacter pylori (H. pylori) gastritis and oro-esophageal candidiasis.

Prevalence of anti- beta2GPI antibodies and their isotypes in patients with renal diseases and clinical suspicion of antiphospholipid syndrome.

BACKGROUND: Antiphospholipid antibodies (aPL) are autoantibodies that are associated with a clinical state of hypercoagulability and diverse clinical manifestations collectively known as antiphospholipid syndrome (APS). OBJECTIVES: To investigate the prevalence of anti-beta2glycoproteinI-antibodies (anti-ß2GPI) and their isotypes in patients with renal diseases and clinical suspicion of antiphospholipid syndrome (APS). PATIENTS AND METHODS: This is a retrospective study in which we have analyzed the prevalence of anti-ß2GPI and its isotypes in 170 patients on initial testing and in 29 patients repeated after 12 weeks for confirmation of APS.  The clinical information was provided by the treating physicians or retrieved from the clinical records. The tests for anti-ß2GPI screening and its isotypes (IgG, IgM and IgA) detection were assessed. RESULTS: On initial samples, anti-ß2GPI was positive in 118patients.  IgA-ß2GPI positivity (93; 79%) was significantly higher than IgM and IgG isotypes.  Out of anti-ß2GPI positive patients, clinical features in 95 patients were suggestive of APS or had SLE.  Of these, IgA isotypes was found in 66% (P = 0.010), IgM in 31% (P = 0.033), and IgG in 11% (P = 0.033). On repeat testing, anti-ß2GPI was persistently found In 22 patients with a continual predominance of IgA-anti-ß2GPI over IgM and IgG isotypes (91% vs. 45.5% and 18% respectively). CONCLUSIONS:   Our results show that IgA-anti-ß2GPI antibodies are the most prevalent isotypes in patients with renal disease or on renal replacement therapy in our population.  Thus inclusion of IgA-anti-ß2GPI in the testing repertoire may increase the diagnostic sensitivity for APS in patients with renal diseases.

Coeliac disease and multiple immunodeficiencies: case report of a diagnostic dilemma.

Coeliac disease (CD) often coexists with other autoimmune and primary immunodeficiency diseases (PID), creating a problem in timely diagnosis and management. An unusual case of coeliac disease that was difficult to diagnose and manage because of its unusual clinical presentation. Initially diagnosed as celiac disease but showed poor response to standard therapy is reported. Frequent attacks of opportunistic infections led to immunodeficiency work-up that revealed natural killer cell (NK) deficiency with low serum IgA and IgG2 levels. The patient eventually succumbed to recurrent infections. The co-existence of PID is unusual in a patient with CD. This case report highlights the importance of investigating PID in patients with autoimmunity.

Relationship of HLA antigens and cryoglobulinaemia in hepatitis C virus infected patients.

OBJECTIVE: To find the relationship between human leukocyte antigens (HLA) and cryoglobulin positivity in hepatitis C virus (HCV) infected individuals. METHODS: Eligible individuals selected from pre and post renal transplant settings were divided into three groups. Group A (n = 301) consisted of normal controls, while group B (n = 200) comprised of pathological controls that were HCV antibody (anti-HCV) positive but negative for cryoglobulins. Group C comprised of 56 anti-HCV positive, cryoglobulin positive patients. HLA-A, -B and -DRB1 loci were typed by polymerase chain reaction (PCR) method and relationship between HLA antigens, anti-HCV status and cryoglobulinaemia was analyzed. RESULTS: HLA-A*02, -B*57 and -DRB1*03 were more frequently found among group C members as compared to groups A and B. Only HLA-B* 57 occurrence reached statistical significance (14.3% versus 6% and 4%, corrected P-value = 0.045 and 0.012 and OR = 2.6 and 4 respectively) No differences in the distribution of HLA antigens were seen among healthy and pathological controls. CONCLUSION: The presence of HLA-B*57 confers susceptibility to cryoglobulinaemia in HCV infected patients in our population. HCV positive renal transplant recipients with these alleles should be monitored for cryoglobulin formation).

Cryoglobulinaemia and autoimmune markers in hepatitis C virus infected patients on renal replacement therapy.

OBJECTIVE: To investigate the association of cryoglobulinaemia and autoimmune markers with hepatitis C virus (HCV) infection in patients on maintenance haemodialysis (HD) and post renal transplantation. METHODS: Serum samples of 103 HCV-antibody (anti-HCV) positive and 105 anti-HCV negative patients were investigated for cryoglobulins. These comprised 136 patients on HD and 72 renal transplant recipients. Serum creatinine and liver function tests were obtained on all patients. Rheumatoid factor (RF), anti nuclear antibodies (ANA), anti smooth muscle antibodies (ASMA), liver kidney microsomal antibodies (LKM), immunoglobulins (Igs) and complement levels were performed on all cryoglobulin positive (cryopositive) samples. HCV RNA and genotyping detection tests were done for cryopositive patients. RESULTS: The prevalence of cryoglobulins in patients on HD or after renal transplantation was found to be higher (57.6%) among anti-HCV positive patients compared to the anti-HCV negative patients (42.4%) (P=0.000). RF, ANA and ASMA were also higher in cryopositive HCV infected patients. HCV RNA was present in 84.2% of anti-HCV positive patients. Cryoprecipitable RF activity was found in a higher number of symptomatic patients with HCV genotype 1 compared to HCV genotype 3. CONCLUSION: There is an association of cryoglobulinaemia and autoimmune markers in HCV infected patients on HD, and in HCV positive renal transplant recipients. Also HCV genotype 1 is associated with symptomatic mixed cryoglobulinaemia.