Patient description: A 17 year old boy complains of vomiting, non-bloody diarrhea, abdominal pain, fever, chills and loss of appetite for the past 3 days. He ate a salad at a restaurant prior to his diarrhea onset. Physical exam was remarkable for pallor, jaundice, and diffuse abdominal tenderness. Lab results were as follows: Hemoglobin: 9.7 g/dL Platelet: 110,000 /cu.mm Creatinine: 3.6 mg/dL blood urea nitrogen (BUN): 73 mg/dL direct bilirubin: 2.4 mg/dL lactate dehydrogenase (LDH): 881 IU/L (normal: 110-265 IU/L) Peripheral blood smear showed a moderate number of schistocytes and helmet cells. Shiga-like toxin-producing E. coli (STEC) stx1/stx2 were found in stools. He has no other underlying disease and he is not on any medications.

Clinical trial eligibility criteria: eligible ages (years): 18.0-999.0,  HIV Infection Liver Failure Evidence of Liver Transplantation Age ≥ 18 Documented HIV-1 infection, hepatitis B or C co-infection is allowed Plasma viral load at screening visit below 50 copies per mL for at least 6 months Patient with severe liver failure (Meld Score ≥ 15 and/or refractory ascites and/or haemorrhage of digestive tract and/or hepatic encephalopathy) for taking part into period 1 Patient eligible for the liver transplant waiting list or immediate post transplantation for taking part into period 2 Abstinence from alcohol intake for at least 6 months (WHO norm) Withdrawal from intravenous drug use for at least 6 months (methadone substitution is permitted) No ongoing class C opportunistic infection (1993 CDC classification) Patient whose clinical and immunovirological condition allows triple therapy with raltegravir + 2 NRTI or raltegravir + NRTI + enfuvirtide Patient whose HIV population, according to cumulative genotypes carried out on viral RNA together with treatment history (if available and interpreted as per the ANRS-AC11 algorithm version no.19) does not present a profile of mutations associated with resistance to raltegravir and is sensitive to at least two fully active* agents selected among nucleoside/nucleotide reverse transcriptase analogs NRTI (abacavir, lamivudine, emtricitabine, tenofovir) or enfuvirtide *An ARV agent is considered to be fully active if the cumulative genotypes do not show any mutation associated with resistance or any mutation associated with "possible resistance"  More than two virological failures during antiretroviral treatment Currently receiving treatment with an agent in development (apart from an authorization for temporary use) Plasma viral load at screening visit ≥ 50 copies per mL during at least the last 6 months Pregnant women, or women liable to become pregnant, breast-feeding women, no contraception, or refusal to use contraception All conditions (including but not limited to alcohol intake and drug use) liable to compromise, in the investigator's opinion, the safety of treatment and/or the patient's compliance with the protocol Patient not having any effective options for NRTI +/ enfuvirtide (defined in the criteria) Ongoing treatment with interferon-alpha or ribavirin for hepatitis C Concomitant medication including one or more agents liable to induce UGT1A1 and reduce raltegravir concentrations anti-infective agents: rifampicin/rifampin