Correction par le lithium des neutropénies induites par la clozapine (deux cas)

Despite the availability of new treatments, the antipsychotic effectiveness of clozapine has not been matched yet. Unfortunately, its regulation is limited by the side effects. The most detrimental is the hematologic toxicity (neutropenia and agranulocytosis) which requires a regular biological monitoring. Treatment with clozapine must be stopped in those cases of secondary granulocytopenia for about 3% of the patients. The current psychiatric drug lithium carbonate has an opposite effect: it can induce leukocytosis. Thus, lithium carbonate is administered in leukopenia, as well as in many hematologic and immunological diseases. However, few teams have used lithium in order to alleviate clozapine-induced granulocytopenia. We report here 2 patients who developed severe neutropenia (neutrophil count<1.5 yen 10 (9)/L) and for whom the use of lithium enabled us to continue the treatment by clozapine. The first patient had a granulocyte rate constitutionally low which rapidly decreased with clozapine. Thanks to the administration of lithium, he recovered quickly a normal blood cell count, which in fact was much higher than his normal rate. According to our research, it's the first time that lithium is reported to be so efficacious in a patient with such a low rate of granulocytes before treatment. It may be that clozapine is not used for those kinds of patients. The second patient developed granulocytopenia after one year of treatment with clozapine. The use of lithium increased so much the number of granulocytes that we continued the treatment with clozapine alone. After 4 months, there is no reappearance of granulocytopenia. We must take into account the partial and contradictory reports in the literature. However, if this result is confirmed, it could be of a high interest to extend the prescription of clozapine, the most effective current antipsychotic drug.

Severe oral ulcerations induced by alendronate

The authors report the case of a 54-year-old man suffering from steroid-induced osteoporosis, who presented with severe oral ulcerations due to sucking alendronate tablets instead of swallowing them. The misuse of alendronate in this case, underlies the risk of direct mucosal injury with this drug.

[Pharmacovigilance in practice]

Directed by the French Agency for the Safety of Health Products (AFSSAPS), the French pharmacovigilance system is in charge of the surveillance of drugs after they have been provided by AFSSAPS with official marketing authorizations that are in France either 'new drug approval certificates' (AMM) or 'temporary utilization authorizations' (ATU). About 3,700 pharmaceutical products are concerned which are used either for treatment (all drugs and remedies, inclusive plasma-derived blood products), prevention (vaccines, oral contraception), diagnosis (contrast products, ...), or to modify a physiologic function (general or local anesthetics). At the national level, the main actors of the system are AFSSAPS and its National Commission, the 31 Regional Centers of Pharmacovigilance, all the health professionnals, and the pharmaceutical laboratories. Health professionnals are held to notify any suspected serious or unexpected adverse effects as quickly as possible. The analysis of data collected by the national report bank permits alerts and inquiries about drug safety. Furthermore regional centers of pharmacovigilance are responsible for drug information. The French pharmacovigilance system works in cooperation with the European Agency for the Evaluation of Medicinal Products.

[Risk related to withdrawal from non-psychotropic drugs]

A review of the available literature concerning sudden withdrawal of drugs shows that withdrawal syndrome have occurred with centrally antihypertensive drugs, beta-blockers on anginal patients, antiparkinsonian drugs and glucocorticoids. Because of a lack of controlled trials led among a large number of individuals, the correct frequency of this withdrawal syndrome is unknown. In most patients, it's hard to distinguish a return to a previous state from an overshoot phenomenon. In that way, gradual and supervised withdrawal of these agents should prevent the complication of sudden cessation of these therapy.

[Severe colectasy in rheumatoid purpura. Probable role of water soluble contrast products]

BACKGROUND

About 60-70% of cases of anaphylactoid purpura suffer from abdominal colic, which may be quite severe. Because severe abdominal pain may be difficult to differentiate from a surgical abdomen, repeated examination and radiological studies are often necessary.

CASE REPORT

A 4 year 7 month-old girl suffered from abdominal pain, vomiting and the skin rash characteristic of anaphylactoid purpura. Because of worsening of the abdominal manifestations, a Gastrografin enema was given. The result was normal but 48 hours later, the child suffered from acute abdominal colics plus symptoms of shock. X-ray examination revealed a large distension of colon and persistence of the contrast material. Exploratory laparotomy failed to find any perforation or necrosis. The colon was drained and the child was given parenteral nutrition and antibiotics. Blood culture showed Klebsiella pneumoniae. An upper gastrointestinal roentgenogram using meglumine ioxitalamate was performed 19 days later because of recurrence of the abdominal pain. This showed a submucosal hemorrhage in the first small bowel loop. Increased abdominal distension occurred 3 days later and the results of X-rays were similar to those seen the Gastrografin enema. A second enema using meglumine ioxitalamate was performed 3 days later. It showed sigmoid constriction but a second laparotomy failed to confirm this obstruction. The child died a few hours later despite ileostomy and antibiotics.

CONCLUSIONS

The severe colectasy seen in this case of anaphylactoid purpura indicates that caution is required in performing enemas in acute digestive complications of this disease. Such X-ray studies should not be repeated and all water-soluble contrast material should be voided as soon as possible.

[Economic impact of adverse drug effects. Some reflections]

The cost of adverse drug effects first began to be analyzed in the 1960s, with an evaluation of related admissions to hospital in the USA. The average cost per patient of adverse events requiring hospitalization in France was estimated at 6,250 F in neurology units in 1979/1980, and 14,920 F in geriatric units in 1984. Fifty per cent of these events were avoidable. A second approach is to measure the cost of certain iatrogenic manifestations, e.g. fever due to fipexide, stenosis and perforation of the small intestine due to potassium chloride, gastrointestinal bleeding due to NSAIDs, kidney damage due to aminosides, etc. Calculations of the economic impact of adverse drug effects must also take into account indirect costs such as loss of productivity. The lack of such studies should not make health care specialists forget the magnitude of the problem.

[Thrombopenia due to pefloxacin (Peflacine): dose-dependent toxicity?]

Pefloxacin (Peflacine) can give rise to thrombocytopenia, although the responsibility of the drug can be difficult to demonstrate in infectious patients and those receiving other drugs simultaneously. We have collated 18 cases in which the responsibility of pefloxacin was suspected. In 13 cases, the patients were also taking other drugs which may have been contributory (heparin, Bactrim, Augmentin, ranitidine,...). The remaining five cases were of particular interest as pefloxacin was the only drug administered. The mean age of the patients was 75 years, and the mean bodyweight 56 kg (range, 47-65 kg). The pefloxacin dosage was 800 to 1,600 mg/day i.v. or p.o., i.e. 13-18 mg/kg/day. Thrombocytopenia occurred from five to 19 days after beginning treatment and resolved between 7 and 12 days after drug withdrawal. A number of factors argue in favor of dose dependency: 1 patient had high plasma concentrations (peak and residual); thrombocytopenia occurred in one patient when the previous, well-tolerated dosage of 800 mg/day (for 15 days) was increased to 1,600 mg/day; thrombocytopenia resolved in one patient when the dosage was reduced to 400 mg/day (1 tablet) and continued for a further 10 days. This toxic reaction may be avoided by reducing the drug dosage to 400 mg/day in elderly patients with a low bodyweight. Differential blood counts appear to be warranted for patients at risk.

[Tolerance of famotidine. Study of network of sentinel physicians in pharmaco-vigilance]

This paper presents the results of an intensive surveillance based on a network of general practitioners and following 200 patients treated by famotidine 40 mg per day during 6 to 8 weeks. Four patients with a previous experience of adverse reaction to another H2 antagonist did not relapse with famotidine. None interaction was reported with drugs such as beta-blockers, oral anticoagulants, theophylline, benzodiazepines, calcium antagonists. Twenty four clinical side effects were reported; For 5 patients (2.5%) the treatment had to be stopped. The most common side effects were neurological. The results are compared with those of previously published studies.

[Prospective OMEGA survey (Drug use-pregnancy relationship survey at the French Riviera)]

The survey of drugs used during pregnancy is necessary and the need for prospective studies is recognized. Health book distribution where drug intake is written since the beginning of the pregnancy allows a narrow therapeutic survey. The 350 first books analysis show that pregnant women use an average of well resorbed 1.8 drugs during 1rst and 3rd pregnancy trimesters. The most commonly used drugs are vitamins and iron (by 56% of women), non-narcotic analgesics (40%), antibiotics (40%), veinotonics (38%) and hormonal treatments (25%).

[Hypersensitivity to hypoglycemic sulfonylurea compounds. Are there cross-reactions?]

We describe 5 observations of cutaneous reactions or immediate hypersensitivity with different hypoglycemic sulfonylurea: Quincke's oedema with glibornuride, three urticaria (one was followed by bronchospasm and collapsus) with glibenclamide, one bullous dermatitis with carbutamide. With special regard to cross reactions between sulfonylurea: we observe the tolerance of glipizide after glibenclamide induced urticaria, tolerance of glicalazide after glibornuride induced Quincke's oedema and eruption, tolerance of glibornuride after chlorporpamide induced urticaria and Quincke's oedema. In the literature, cross reactions between 1st generation sulfonylurea are noted, but not cross reactions between 1st and 2nd generation.