Herbalife hepatotoxicity: Evaluation of cases with positive reexposure tests

Table 4 Analysis of positive reexposure tests in cases with suspected Herbalife hepatotoxicity

Cases with initially suggested positive reexposure tests

Case 1

The 63-yr old woman used a Herbalife product and experienced a positive reexposure test that was fairly well documented, but duration of product reuse was insufficiently communicated[1]. Upon first challenge, ALT was 1897 U/L and declined to 35 U/L after product discontinuation. Rechallenge increased ALT 758 U/L. Since ALTb is < 5 N and ALTr ≥ 2 ALTb, this ascertains the positive reexposure test

Case 2

The 55-yr old woman consumed Herbalife products. Liver disease by not further specified liver values as well as a positive reexposure test was described[2]. Individual ALT values were not presented, hence data required for criteria of ALTb < 5 N and ALTr ≥ 2 ALTb are not available. The data are uninterpretable regarding the claimed positive reexposure test

Case 3

The 48-yr old woman was on Herbalife products, when hepatocellular hepatitis was diagnosed associated with a positive reexposure test[2]. Lack of any specific ALT values prevented establishing criteria of ALTb < 5 N and ALTr ≥ 2 ALTb. The case is uninterpretable with respect to the reexposure test

Case 4

The 78-yr old woman used Herbalife products and was diagnosed with hepatocellular liver injury based on liver values[2]. A positive reexposure test was described, but details of the test and individual ALT values were not provided. Therefore, criteria of ALTb < 5 N and ALTr ≥ 2 ALTb cannot be ascertained. The case is uninterpretable due to lacking test criteria.

Case 5

The 30-yr old man consumed Herbalife products and experienced a biopsy proven liver disease[3]. A positive reexposure test was described, but details were not provided. An initial ALT value was reported with lack of ALT data in the further course including the reexposure test, preventing the confirmation of the essential criteria ALTb < 5 N and ALTr ≥ 2 ALTb. Lack of these criteria leads to uninterpretable data of the test

Case 6

The 44-yr old woman used Herbalife products, experienced jaundice with increased ALT 2637 U/L[4]. Following product cessation, normalization of liver values reported, but actual ALT values were not presented. After Herbalife reuse, rise of liver values was communicated, but no details of actual ALT values given. ALTb is probably < 5 N, but ALTr is unknown. Currently, this case is uninterpretable regarding the reexposure test

Case 7

The 39-yr old woman was on Herbalife products and experienced a hepatitis, which improved after product cessation, but actual ALT values before reexposure are not communicated[5]. Recurrent increase of ALT was reported, but actual values not presented. Since ALTb and ALTr are unknown, the reexposure test is uninterpretable

Case 8

The 49-yr old woman used Herbalife products and experienced an ALT of 922 U/L, which dropped after product cessation to 793 U/L and rose to 1500 U/L after reintroduction[5]. ALTb is ≥ 5 N and ALTr < 2 ALTb, the test is negative

Cases with initially questionable positive reexposure tests

The 60-yr old man was reported with use of Herbalife products, a histology proven liver disease, and a questionable positive rechallenge[3]. When an increase of liver values was again observed, the patient denied Herbalife consumption. Thus, no evidence for a positive reexposure test exists

The 41-yr old woman was on a Herbalife product and suffered from fulminant hepatic failure requiring liver transplantation[3]. A questionable positive reexposure test with slightly elevated liver enzymes lacking actual ALT values was described for the transplanted liver one year after transplantation, when the patient was vague about Herbalife use. Therefore, clear evidence for a positive reexposure test is missing

The eight cases correspond to those presented in Table 1, and the data of the two cases with initially questionable positive reexposure tests are derived from the literature. Required data are alanine aminotransferase (ALT) levels at baseline before reexposure, designed ALTb, and ALT levels during reexposure, designed ALTr. Response to reexposure is positive, when ALTb < 5 N and ALTr ≥ 2 ALTb. Criteria are applicable for the hepatocellular type if liver injury. N: Upper limit of normal.