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False-positive HIV-1 ELISA in patients with hepatitis B

2002; Elsevier BV; Volume: 112; Issue: 9 Linguagem: Inglês

10.1016/s0002-9343(02)01113-0

1555-7162

Chun Tao Wai, Paul Anantharajah Tambyah,

HIV Research and Treatment

Human immunodeficiency virus (HIV) testing is often part of the workup of patients admitted to acute care hospitals. While enzyme-linked immunosorbent assay (ELISA) testing for HIV has a sensitivity and specificity greater than 99% (1Mylonakis E. Paliou M. Lally M. et al.Laboratory testing for infection with the human immunodeficiency virus established and novel approaches.Am J Med. 2000; 109: 568-576Abstract Full Text Full Text PDF PubMed Scopus (88) Google Scholar), physicians should be aware of its limitations. False-positive tests have been reported in multiparous women; persons recently vaccinated against influenza or hepatitis B; patients who have had multiple blood transfusions; and those with autoimmune disease, cirrhosis due to alcohol use, malaria, and dengue virus infection (2Proffitt M.R. Yen-Lieberman B. Laboratory diagnosis of human immunodeficiency virus infection.Infect Dis Clin North Am. 1993; 7: 203-219Abstract Full Text PDF PubMed Google Scholar, 3Celum C.L. Coombs R.W. Jones M. et al.Risk factors for repeatedly reactive HIV-1 EIA and indeterminate western blots.Arch Intern Med. 1994; 154: 1129-1137Crossref PubMed Scopus (68) Google Scholar). We describe two cases of false-positive HIV-1 ELISA related to hepatitis B virus infection.The first patient was a 40-year-old, previously healthy man who was admitted with a 2-week history of right upper quadrant pain, fever, and malaise. Liver function tests showed acute hepatitis with an alanine aminotransferase (ALT) level of 2597 U/L (normal <70 U/L) and an aspartate aminotransferase (AST) level of 681U/L (normal <50 U/L). Bilirubin level and prothrombin time were normal. Diagnosis of acute hepatitis B was made on the basis of a positive hepatitis B surface antigen and anti-hepatitis B core immunoglobulin M. On further questioning, he admitted having unprotected sexual intercourse with a new female partner 4 months before the onset of jaundice. HIV serology, which was performed after informed consent was obtained, was positive by ELISA (Axysym, Abbott Laboratories, Abbott Park, Illinois). Confirmatory tests with Western blot (HIV Blot 2.2, Gene Lab Diagnostics, Singapore) and p24 antigen (Elecsys 2010 System, Roche Diagnostics Corporation, Indianapolis, Indiana), however, were negative. Further clinical evaluation did not show any oral lesions, peripheral lymphadenopathy, or evidence of an acute retroviral syndrome. The patient had a persistently positive HIV ELISA, with negative HIV Western blots and HIV p24 antigen at 3, 7, and 12 months after the initial presentation. His liver function tests normalized, and he cleared his hepatitis B surface antigen and developed anti-hepatitis B surface antibody.The second patient was a 58-year-old man who had chronic hepatitis B infection and who was admitted because of liver failure and encephalopathy. He was noted to have had jaundice 1 month before admission. Physical examination showed asterixis and jaundice. He had an elevated prothrombin time of 31 seconds, a bilirubin level of 361 μmol/L (normal <30 μmol/L), and an ALT level of 735 U/L. While being evaluated for liver transplantation, he was found to be positive for HIV by ELISA. Confirmatory tests with Western blot and p24 antigen were negative. As he was encephalopathic, we were not able to identify risk factors for HIV infection. Despite intensive care that included liver dialysis, his liver function continued to deteriorate and he died of acute liver failure 11 days after admission.False-positive results led to management problems in these patients. With the first patient, who had a high pretest probability for HIV infection, he was advised to use barrier methods while having sexual intercourse with his wife during the prolonged observation period because of concerns about delayed HIV seroconversion, which has been reported with hepatitis C virus coinfection (4Ridzon R. Gallagher K. Ciesielski C. et al.Simultaneous transmission of human immunodeficiency virus and hepatitis C virus from a needle-stick injury.N Engl J Med. 1997; 336: 919-922Crossref PubMed Scopus (136) Google Scholar). The second patient had acute liver failure and was considered for liver transplantation because of a rising prothrombin time, which is a prognostic factor in Asian patients with acute exacerbations of hepatitis B (5Wai C.T. Chan E. Lee Y.M. et al.Prognostic factors for acute exacerbation of chronic hepatitis in Asian patients.J Hepatol. 2001; 34: S135Abstract Full Text PDF Google Scholar). However, the decision for transplantation was delayed while awaiting HIV confirmatory results, and the patient died soon after admission.These patients with false-positive results related to concurrent acute hepatitis B infection and acute exacerbation of chronic hepatitis B highlight the limitations of ELISA tests for HIV. Physicians should be aware of false-positive results, especially since there is considerable overlap of hepatitis B and HIV epidemiology, and particularly in areas where further testing might not be routinely recommended. Human immunodeficiency virus (HIV) testing is often part of the workup of patients admitted to acute care hospitals. While enzyme-linked immunosorbent assay (ELISA) testing for HIV has a sensitivity and specificity greater than 99% (1Mylonakis E. Paliou M. Lally M. et al.Laboratory testing for infection with the human immunodeficiency virus established and novel approaches.Am J Med. 2000; 109: 568-576Abstract Full Text Full Text PDF PubMed Scopus (88) Google Scholar), physicians should be aware of its limitations. False-positive tests have been reported in multiparous women; persons recently vaccinated against influenza or hepatitis B; patients who have had multiple blood transfusions; and those with autoimmune disease, cirrhosis due to alcohol use, malaria, and dengue virus infection (2Proffitt M.R. Yen-Lieberman B. Laboratory diagnosis of human immunodeficiency virus infection.Infect Dis Clin North Am. 1993; 7: 203-219Abstract Full Text PDF PubMed Google Scholar, 3Celum C.L. Coombs R.W. Jones M. et al.Risk factors for repeatedly reactive HIV-1 EIA and indeterminate western blots.Arch Intern Med. 1994; 154: 1129-1137Crossref PubMed Scopus (68) Google Scholar). We describe two cases of false-positive HIV-1 ELISA related to hepatitis B virus infection. The first patient was a 40-year-old, previously healthy man who was admitted with a 2-week history of right upper quadrant pain, fever, and malaise. Liver function tests showed acute hepatitis with an alanine aminotransferase (ALT) level of 2597 U/L (normal <70 U/L) and an aspartate aminotransferase (AST) level of 681U/L (normal <50 U/L). Bilirubin level and prothrombin time were normal. Diagnosis of acute hepatitis B was made on the basis of a positive hepatitis B surface antigen and anti-hepatitis B core immunoglobulin M. On further questioning, he admitted having unprotected sexual intercourse with a new female partner 4 months before the onset of jaundice. HIV serology, which was performed after informed consent was obtained, was positive by ELISA (Axysym, Abbott Laboratories, Abbott Park, Illinois). Confirmatory tests with Western blot (HIV Blot 2.2, Gene Lab Diagnostics, Singapore) and p24 antigen (Elecsys 2010 System, Roche Diagnostics Corporation, Indianapolis, Indiana), however, were negative. Further clinical evaluation did not show any oral lesions, peripheral lymphadenopathy, or evidence of an acute retroviral syndrome. The patient had a persistently positive HIV ELISA, with negative HIV Western blots and HIV p24 antigen at 3, 7, and 12 months after the initial presentation. His liver function tests normalized, and he cleared his hepatitis B surface antigen and developed anti-hepatitis B surface antibody. The second patient was a 58-year-old man who had chronic hepatitis B infection and who was admitted because of liver failure and encephalopathy. He was noted to have had jaundice 1 month before admission. Physical examination showed asterixis and jaundice. He had an elevated prothrombin time of 31 seconds, a bilirubin level of 361 μmol/L (normal <30 μmol/L), and an ALT level of 735 U/L. While being evaluated for liver transplantation, he was found to be positive for HIV by ELISA. Confirmatory tests with Western blot and p24 antigen were negative. As he was encephalopathic, we were not able to identify risk factors for HIV infection. Despite intensive care that included liver dialysis, his liver function continued to deteriorate and he died of acute liver failure 11 days after admission. False-positive results led to management problems in these patients. With the first patient, who had a high pretest probability for HIV infection, he was advised to use barrier methods while having sexual intercourse with his wife during the prolonged observation period because of concerns about delayed HIV seroconversion, which has been reported with hepatitis C virus coinfection (4Ridzon R. Gallagher K. Ciesielski C. et al.Simultaneous transmission of human immunodeficiency virus and hepatitis C virus from a needle-stick injury.N Engl J Med. 1997; 336: 919-922Crossref PubMed Scopus (136) Google Scholar). The second patient had acute liver failure and was considered for liver transplantation because of a rising prothrombin time, which is a prognostic factor in Asian patients with acute exacerbations of hepatitis B (5Wai C.T. Chan E. Lee Y.M. et al.Prognostic factors for acute exacerbation of chronic hepatitis in Asian patients.J Hepatol. 2001; 34: S135Abstract Full Text PDF Google Scholar). However, the decision for transplantation was delayed while awaiting HIV confirmatory results, and the patient died soon after admission. These patients with false-positive results related to concurrent acute hepatitis B infection and acute exacerbation of chronic hepatitis B highlight the limitations of ELISA tests for HIV. Physicians should be aware of false-positive results, especially since there is considerable overlap of hepatitis B and HIV epidemiology, and particularly in areas where further testing might not be routinely recommended.