[Pseudo-pheochromocytoma due to iproniazid: A case report]. / Pseudo-phéochromocytome médicamenteux sous iproniazide : à propos d'un cas.

INTRODUCTION: Pheochromocytoma is suggested by the presence of severe and paroxysmal hypertension associated with hyperadrenergy clinical signs. If the diagnosis of pheochromocytoma is ruled out, a pseudo-pheochromocytoma should be considered. We report a clinical observation of pseudo-pheochromocytoma due to iproniazid, a non-selective irreversible monoamine oxidase (MAO) A and B inhibitor in a patient with bipolar disorder. CASE REPORT: A 78-year-old Caucasian male patient treated by iproniazid was hospitalized for depressive relapse. After several episodes of syncopes related to orthostatic hypotension, the patient presented hypertensive crisis. Urinary normetanephrines were increased to twice the upper limit of the normal range. Iproniazid was discontinued. Patient hemodynamic was rapidly stabilized and sympathetic hypertonia diminished. The urinary measurements normalized within two months. The abdominal imaging eliminated an adrenal tumor. CONCLUSION: Iproniazid could be responsible for severe irregular blood pressure associated with abnormal catecholamine metabolism (i.e. pseudo-pheochromocytoma).

[Auxiliary hepatic transplantation in iproniazid-induced subfulminant hepatitis. Should iproniazid still be sold in France?]. / Transplantation hépatique auxiliaire pour hépatite subfulminante à l'iproniazide. Doit-on maintenir la commercialisation de l'iproniazide en France?

We report a new case of subfulminant hepatitis due to iproniazid, a MAO-inhibitor antidepressant, in a 27-year-old man. An auxiliary liver transplantation was performed. Liver function returned to normal and the patient was discharged from the hospital. However, the patient's native liver did not regenerate, and immunosuppressive therapy had to be maintained. Iproniazid hepatotoxicity is characterized by jaundice in 1% of cases, with a fulminant or subfulminant course in 20% of icteric patients. Although iproniazid is no longer sold in most countries, it is still commercialized in France. Because of the frequency and severity of hepatic injury, commercialization of iproniazid in France should no longer be authorized.

Drug-induced immunotoxicity.

Immune-related drug responses are one of the most common sources of idiosyncratic toxicity. A number of organs may be the target of such reactions; however, this review concentrates mostly on the liver. Drug-induced hepatitis is generally divided into two categories: acute hepatitis in which the drug or a metabolite destroys a vital target in the cell; immunoallergic hepatitis in which the drug triggers an adverse immune response directed against the liver. Their clinical features are: a) low frequency; b) dose independence; c) typical immune system manifestations such as fever, eosinophilia; d) delay between the initiation of treatment and onset of the disease; e) a shortened delay upon rechallenge; and f) occasional presence of autoantibodies in the serum of patients. Such signs have been found in cases of hepatitis triggered by drugs such as halothane, tienilic acid, dihydralazine and anticonvulsants. They will be taken as examples to demonstrate the recent progress made in determining the mechanisms responsible for the disease. The following mechanisms have been postulated: 1) the drug is first metabolized into a reactive metabolite which binds to the enzyme that generated it; 2) this produces a neoantigen which, once presented to the immune system, might trigger an immune response characterized by 3) the production of antibodies recognizing both the native and/or the modified protein; 4) rechallenge leads to increased neoantigen production, a situation in which the presence of antibodies may induce cytolysis. Toxicity is related to the nature and amount of neoantigen and also to other factors such as the individual immune system. An effort should be made to better understand the precise mechanisms underlying this kind of disease and thereby identify the drugs at risk; and also the neoantigen processes necessary for their introduction into the immune system. An animal model would be useful in this regard.

Human anti-mitochondria autoantibodies appearing in iproniazid-induced immunoallergic hepatitis recognize human liver monoamine oxidase B.

Anti-mitochondria (anti-M6) autoantibodies have been found in the serum of patients with immunoallergic iproniazid (Marsilid)-induced hepatitis, but to date the identity of the protein antigen has not been determined. Here we show, using immunoprecipitation of pargyline-labelled proteins, that among the mitochondrial proteins, liver MAO-B is specifically recognized by the sera containing anti-M6 antibodies. Moreover the enzymatic activity of MAO-B towards phenylethylamine and tyramine is also suppressed after this immunoprecipitation, contrary to the MAO-A activity towards 5-hydroxy-tryptamine. As MAO is irreversibly inhibited by iproniazid, these results suggest that the mechanism of iproniazid-induced appearance of anti-M6 antibodies could be another example of the reactive metabolite/enzyme haptenization mechanism already proposed in the case of tienilic acid for the appearance of anti-organelle antibodies in a drug-induced hepatitis.

[Iproniazid-induced acute hepatitis]. / Epatite acuta da iproniazide.

Many drugs can cause an acute liver damage. The patient history is the guideline for diagnosis. Iproniazid, a monoamine-oxidase inhibitor not for sale in Italy, can frequently cause severe acute hepatitis. A case of acute iproniazid-induced, hepatitis in which the course was favourable, is reported.

A comparative trial of a MAOI, iproniazide, and a polycyclic agent, mianserine, for the search of the most rapidly and frequently active treatment of depressive syndromes in an oncology service.

Many cancer patients of the "Service des Maladies Sanguines et Tumorales" of Hôpital Paul-Brousse, Villejuif, are psychologically studied by: the objective and quantified Szondi test, and in the case a depressive syndrome clinical diagnosis is confirmed, this state is quantified by a quintile questionnaire requiring 25 "yes or no" answers (determined by five grades and five stages), in case an inhibition or/and hysteric component is found, the subjects are submitted to the care of a psychoanalyst. A comparative trial of the MAOI, iproniazide, and the tetracyclic analog, mianserine, has been conducted for the search of the most frequently and rapidly active antidepressant agent among them both. The hypothesis that mianserine is less frequently and rapidly active than iproniazide was drawn from our previous experience of 20 years: thus patients presenting a score less than or equal to 12/25 were given mianserine (20 up to 30 mg/day to be possibly increased according to medical decision), while those presenting a score greater than or equal to 13/25 received iproniazide (50 up to 75 mg/day). The patients who failed with mianserine received iproniazide, while those who failed with iproniazide were supposed to receive mianserine. The registered results are the following: a) out of the 25 patients with major depressive syndromes (score greater than or equal to 13) submitted to iproniazide, 16 (61%) were in complete remission (score at 0/25) and five in partial regression (score decreased by more than half); this makes 21 responses in all, i.e. 80%, obtained between the 10th and the 30th days, which is superior to all placebo responses which have varied in the reliable literature from 13 to 70%; b) out of 18 depressive patients submitted to mianserine, only one had benefited of a complete remission and four of a partial regression at the 30th day, which makes 28% responses. Among the side effects of iproniazide, they were two colon meteorism syndromes, easily corrected by prostigmine, five hyposomnia cases corrected by dipotassium chlorazepate, four anejaculation or delay at ejaculation cases which needed eserine when the patients require their disappearance or attenuation. We did not register either hepatic or hyperthermic or hypertensive complications: this is in good agreement with the true incidences, especially that of hypertensive crisis which could be found in serious and scientifically documented articles, to be 0.3 to 0.5% for their appearance, and 1 per 100,000 for their fatal evolution. Among the side effects of mianserine, we have not registered any of the hepatic, renal and cardiac complications mentioned in the literature.(ABSTRACT TRUNCATED AT 400 WORDS)

Drug-induced hepatitis associated with anticytoplasmic organelle autoantibodies.

A study from five hepatology units documenting 157 cases of drug-induced hepatitis and a second study from a laboratory of immunology which tested more than 100,000 sera permitted us to establish the frequency of antiorganelle antibodies and their diagnostic value in drug-induced hepatitis. In drug-induced hepatitis caused by a heterogenous group of drugs consisting of ajmaline, aminopterine, isaxonine, isoniazid, perhexiline, phenylbutazone and troleandromycine, antiorganelle antibodies were absent or rare. In drug-induced hepatitis caused by another heterogenous group of drugs, including clometacin, fenofibrate, oxyphenisatin and papaverine, antismooth muscle, antinucleus and antimitochondria antibodies were found in isolation or in different combinations in 70% of cases. From the presence of antismooth muscle antibodies in sera, we could trace 30 cases of clometacin-induced hepatitis. The third group included drug-induced hepatitis with special antibody:iproniazid-induced hepatitis with antimitochondrial antibody 6 and tienilic acid (ticrynafen)-induced hepatitis with antiliver/kidney microsome antibody 2 (anti-LKM2). These two antibodies are rare in routine sera and were absent in patients who received the drug and had no liver damage. From the presence of corresponding antibodies, we detected six cases of iproniazid-induced hepatitis and 67 cases of tienilic acid-induced hepatitis. Antiorganelle antibodies found in high titers disappeared in 2 to 24 months following withdrawal of the offending drug. The fourth group was represented by halothane-induced hepatitis; antiliver/kidney microsome antibody 1 was weak and infrequent. Similarities between drug-induced hepatitis of the second group and lupoïd hepatitis suggest that drugs may reveal this spontaneous disorder.(ABSTRACT TRUNCATED AT 250 WORDS)

Monoamine oxidase inhibitors and alprazolam in the treatment of panic disorder and agoraphobia.

This article reviews the evidence on the efficacy of monoamine oxidase inhibitors (MAOIs) and of alprazolam in the treatment of panic disorder and agoraphobia. It also presents guidelines to the clinician on how to implement these treatments in practice.

[Autoimmunity induced by drugs. Immunological characteristics and etiopathogenic hypotheses]. / Auto-immunité induite par les médicaments. Particularités immunologiques et hypothèses étiopathogéniques.

Drug-induced autoimmune diseases have two immunological peculiarities. Firstly, some autoantibodies are present, which are virtually never seen in spontaneous human diseases and may be regarded as specific. This applies to antimitochondria antibody type 3 (anti M3) in the lupus-like syndrome caused by Venocuran, to antimitochondria antibody type 6 (anti M6) in iproniazide-induced hepatitis, to anti-insulin antibody found after treatment with methimazole, and to anti liver/kidney microsome antibody type 2 (anti LKM2) associated with hepatitis induced by tielinic acid. Secondly, a search for other autoantibodies shows that the immune disorder is much more limited than in spontaneous autoimmune diseases. Thus, contrary to myasthenia and idiopathic autoimmune haemolytic anaemia, we never found autoantibodies specifically directed against the thyroid, the stomach or the adrenal gland during treatment with D-penicillamine and alpha-methyldopa. Only some hypotheses may account for these peculiarities. Cross-reaction between drug and autoantigen may occur, but the fact that the antigen-antibody reaction is not inhibited by the drug or its metabolites does not support this explanation. Much more attractive is the "T-cell bypass" theory, according to which autoreacting suppressor T-cells are circumvented by helper T-cells stimulated by the drug-modified autoantigen. In this case, the autoimmune reaction would indicate to which body substance the drug is bound, thus making it immunostimulant, and not a structural similarity between the drug and the autoantigen.

[Iproniazid-induced hepatitis. The diagnostic value of a new antimitochondrial antibody anti-M6]. / Hépatite à l'iproniazide. Intérêt diagnostique d'un nouvel anticorps antimitochondrial, l'anti-M6.

The authors report the observations of four patients with iproniazid hepatitis. Three of these patients died. An antimitochondrial antibody was found in the 4 patients at a high titer. This antibody differed from the antimitochondrial antibodies which have been described previously (anti-M1, anti-M5). This new antibody was called anti-M6. The evolution of the anti-M6 titer has been studied in the patient who survived. This titer progressively decreased; the antibody was no longer detectable 6 months after the withdrawal of iproniazid. Anti-M6 has not been found in other hepatic diseases. It was not detected in 15 patients receiving iproniazid without hepatitis or in 6 patients receiving isoniazid. Anti-M6 appears as a useful serologic marker for the diagnosis of iproniazid hepatitis.

A new antimitochondria antibody (anti-M6) in iproniazid-induced hepatitis.

A new immunofluorescence pattern of non-organ- and non-species-specific antibody has been observed in occasional sera. Variations of the fluorescence were found in different species. Recognition of the new pattern was particularly characteristic in rat organs (liver: the hepatocytes showed intense roughly granular fluorescence evenly distributed in the cytoplasm; kidney: the bright fluorescence of the first portion of the proximal tubules contrasted with the negative aspect of the other portions of the tubules; stomach: only some cells probably corresponding to the APUD system were positive; pancreas: fluorescence was limited to the islets of Langherhans). The positivity in the ellipsoid region of the rods and cones of the eye and the absorption on different liver organelles showed that this aspect corresponded to the mitochondria. We propose to name this pattern 'antimitochondria antibody number 6' or 'anti-M6'. High titres of anti-M6 were found in four patients suffering from iproniazid-induced hepatitis. A decrease in the titre was obtained after stopping the treatment. The now exceptional use of iproniazid and the rare occurrence of anti-M6 suggest a link between these two phenomena.

Iproclozide fulminant hepatitis. Possible role of enzyme induction.

The authors report the cases of 3 patients who died from fulminant hepatitis after receiving iproclozide, a hydrazine-containing monoamine oxidase inhibitor. Fulminant hepatitis in these patients resembled that reported in patients receiving other hydrazine-containing monoamine oxidase inhibitors: (1) the 3 patients were women; (2) the monoamine oxidase inhibitor has been ingested for 1 month or more; (3) the main clinical manifestations were jaundice and disorders of consciousness; (4) hypersensitivity manifestations were absent; (5) the predominant liver lesion was necrosis; (6) all 3 patients died. In our 3 patients, jaundice occurred 7 to 10 days after the adjunction to iproclozide of a microsomal enzyme inducer. These observations suggest that concomitant administration of iproclozide and of microsomal enzyme inducers may produce fulminant hepatitis in man. It is speculated that iproclozide could be, like iproniazid, transformed into a hepatotoxic metabolite, the production of which would be increased by microsomal enzyme induction.