Hans E. Persson

Poisoning severity score. Grading of acute poisoning.

BACKGROUND A standardized and generally applicable scheme for grading the severity of poisoning allows a qualitative evaluation of morbidity and facilitates comparability of data. Working from a simple grading scale proposed by the European Association of Poisons Centres and Clinical Toxicologists, a Poisoning Severity Score has been developed jointly with the International Programme on Chemical Safety and the European Commission. METHODS The Poisoning Severity Score has been elaborated, tested, and gradually revised during a project running 1991-1994. Fourteen poisons centers from various countries have participated. Each center independently graded 371 cases of acute poisoning by ten different toxic agents. The data were then analyzed and compared. RESULTS The concordance in grading the severity increased during the study period, and in the last phase there was an acceptable concordance among centers in 80% or more of the cases. Given the condition and quality of the original case records, this result was considered satisfactory and agreement was reached on the scoring scheme presented here. The Poisoning Severity Score grades severity as (0) none, (1) minor, (2) moderate, (3) severe, and (4) fatal poisoning. It is intended to be an overall evaluation of the case, taking into account the most severe clinical features. Use of the Poisoning Severity Score normally requires a follow-up of all cases, but may be used on admission or other times during the course of poisoning if this is clearly stated when data are presented. CONCLUSIONS A Poisoning Severity Score has been developed and found applicable for grading the severity of poisoning. It is foreseen that the Poisoning Severity Score will meet the expectations and be used in practice, but its future use and evaluation may result in some further revision and refinement.

Cytotoxic fungi--an overview.

Among fungal toxins causing organ damage in the human body, amatoxins and orellanine remain exceptional. Amatoxins, a group of bicyclic octapeptides occurring in some Amanita, Galerina and Lepiota species, induce deficient protein synthesis resulting in cell death, but might also exert toxicity through inducing apoptosis. Target organs are intestinal mucosa, liver and kidneys. Poisoning will result in dehydration and electrolyte derangement, liver necrosis and possibly kidney damage. In established poisoning the mainstay of treatment is optimum symptomatic and supportive care. No specific treatment is available, but some pharmaceuticals, like silibinin, benzylpenicillin and acetylcysteine, might have a role in limiting the extent of hepatic damage. Orellanine is a nephrotoxic bipyridine N-oxide found in some Cortinarius species. Its mechanism of action is not fully understood, but it has been shown to inhibit protein synthesis and to generate free oxygen radicals. As early symptoms often are lacking or vague, poisoning may initially be overlooked or misinterpreted and the patients usually present with established renal damage. Supportive care is the only therapeutic option. Tricholoma equestre might contain a myotoxin and repeated ingestion may cause significant rhabdomyolysis. Ingestion of Amanita smithiana and A. proxima has been reported to result in kidney damage. Gyromitrin, a toxic compound that is converted to hydrazines in the stomach, occurs in some Gyromitra species. It is mainly neurotoxic, but may also induce moderate hepatic damage and haemolysis.

Acute Plant Poisoning and Antitoxin Antibodies

Plant poisoning is normally a problem of young children who unintentionally ingest small quantities of toxic plants with little resulting morbidity and few deaths. In some regions of the world, however, plant poisonings are important clinical problems causing much morbidity and mortality. While deaths do occur after unintentional poisoning with plants such as Atractylis gummifera (bird-lime or blue thistle) and Blighia sapida (ackee tree), the majority of deaths globally occur following intentional self-poisoning with plants such as Thevetia peruviana (yellow oleander) and Cerbera manghas (pink-eyed cerbera or sea mango). Antitoxins developed against colchicine and cardiac glycosides would be useful for plant poisonings—anti-digoxin Fab fragments have been shown to be highly effective in T. peruviana poisoning. Unfortunately, their great cost limits their use in the developing world where they would make a major difference in patient management. Therapy for some other plant poisonings might also benefit from the development of antitoxins. However, until issues of cost and supply are worked out, plant antitoxins are going to remain a dream in many of the areas where they are now urgently required.

A Nationwide Study of Vipera Berus Bites During One Year—Epidemiology and Morbidity of 231 Cases

Objectives. To describe clinical course, influence of treatment, and epidemiology of Vipera berus envenomation in a defined population, and to compare the results with those of a similar, nationwide study in 1975. Design. Retrospective case review study. Setting and subjects. Case records regarding all patients treated in Swedish hospitals during 1995 for bites by the common European adder, V. berus, were studied. A severity grading was applied. Possible dropout was fewer than 10 patients. Results. A total of 231 inpatients were treated for V. berus bites in Sweden in 1995. Children less than 10 years old were overrepresented and there was a slight predominance for males. Maximum severity of envenomation was none in 11%, minor in 47%, moderate in 29%, and severe in 13% of the cases. A few patients with initially minor or moderate symptoms eventually met the criteria of severe envenomation. Less commonly reported features were pulmonary edema, generalized plasma leakage, seizures, deep venous thrombosis, compartment syndrome, numbness and paraesthesia, and myocardial infarction. Treatment included antivenom in 42 patients [ovine Fab in 30 and equine F(ab9)2 in 12 cases]. Systemic symptoms resolved during or shortly after the antivenom infusion. Extensive edema involving the trunk occurred in 5% of the cases in 1995, whereas 14% of the patients had extensive swelling in 1975. Conclusions. Incidence and other epidemiological data were similar to those 20 years ago, whereas the clinical course was more benign. It seems reasonable to believe that this is due to the introduction of effective antivenoms.

Ethylene glycol poisoning: experiences from an epidemic in Sweden

In 1987 two lethal adult cases of accidental ethylene glycol poisoning were given spectacular attention in the Swedish mass media. This resulted in an epidemic of intentional ethylene glycol poisonings. In addition to six cases related to alcohol abuse, another 30 severe suicidal poisonings were reported to the Swedish Poison Information Centre in five months. The clinical course and outcome in these 36 severe cases are reviewed. The primary clinical manifestations were metabolic acidosis, CNS disturbances and kidney damage with circulatory failure in the most severe cases. Mortality was 17%. Fragmentation of the normal striation in heart cells was found in two of the fatal cases and severe brain damage in all fatal poisonings. The degree of acidosis but not the serum ethylene glycol level correlated with both kidney damage and outcome. Treatment included ethanol, correction of the metabolic acidosis and dialysis. Four patients with serum ethylene glycol concentrations of 10-20 mmol/L (620-1240 mg/L) but with no or minimal metabolic acidosis were treated with ethanol alone; none of these patients developed renal damage.

Simulated Long-Term Driving Performance before and after Uvulopalatopharyngoplasty

To investigate whether automobile drivers with the clinical features of sleep apnea syndrome (SAS) perform worse than controls in a simulated long-term test drive, and to see if their driving improves after uvulopalatopharyngoplasty (UPPP), 15 male drivers with SAS, suffering from sleep spells whilst driving, and 10 matched controls without a history of SAS or hypersomnia at the wheel were tested in an advanced driving simulator. Brake reaction time, lateral position deviation and off-road episodes were measured during a 90-min rural drive at twilight conditions. The clinical evaluation was made by a questionnaire scoring symptoms of snoring, sleep disturbances and diurnal sleepiness before and after surgery. Before UPPP the patient group showed impaired performance in all three effect measures compared to controls. UPPP resulted in improved reaction time performance (average mean improvement: 0.5 s, average 90th percentile improvement 0.8 s). Furthermore, 12 of the 15 patients reported a marked improvement regarding sleepiness whilst driving. For these clinically successful cases the number of off-road episodes decreased substantially. We conclude that most patients improve their long-term driving performance as a result of UPPP.

Menstruation‐related periodic hypersomnia A case study with successful treatment

A 16-year-old girl suffered from 1 to 2-week periods of hypersomnia associated with each menstruation. Serum hormone levels were normal. CSF concentrations of homovanillic acid and 5-hydroxyindolacetic acid were lower in hypersomniac than in symptom-free phases. 3-methoxy-4-hydroxyphenylethylene glycol was not affected. The sleep periods occurred only in connection with ovulatory menstrual cycles. When ovulation was inhibited by a combination of ethinylestradiol and lynestrenol, an oral contraceptive pill, the hypersomnia ceased. Thus, the hypersomnia seemed to be linked to the occurrence of ovulatory menstruations.

Development and clinical application of immunoassays for European adder (Vipera berus berus) venom and antivenom

An ovine affinity purified Fab antivenom was used in a clinical trial in Sweden to treat European adder (Vipera berus berus) envenoming. Immunoassays were developed to measure V. b. berus venom and antivenom concentrations in clinical samples to help assess the efficacy of treatment. A radioimmunoassay (RIA) was developed, optimized and validated to measure plasma levels of V. b. berus venom and compared with a conventional ELISA. Both showed a similar variation of zero binding in biological samples and the results obtained correlated closely. However, the ELISA was quicker and more sensitive (0.8 compared with 2 micrograms/litre). Before administration of antivenom, V. b. berus venom concentrations in plasma ranged from 10 to 53 micrograms/litre; 12 hr after the Fab infusion, no patient had measurable levels. However, two patients had low venom levels 24 hr after treatment. ELISA and RIA were also developed, optimized and used to measure concentrations of free Fab in plasma. There was a biexponential fall of Fab concentration with a fast distribution phase (t 1/2 = 0.9 hr) and a slower elimination phase (t 1/2 = 18 hr). The amount of Fab excreted in urine was low.

Provoked visual impairment in multiple sclerosis studied by visual evoked responses.

Pattern-reversal VERs were studied during the visual impairment provoked by exercise in 2 patients with demyelinating optic neuritis. It was found that the transient reduction in visual acuity was correlated to a transient decrease in the amplitude of the major positive component of the VER, whereas no significant changes could be observed in the latency of the response. The normal VER was not influenced by exercise.