Human exposures to stinging caterpillar: Lophocampa caryae exposures

The purpose of this project was to characterize the presentation and treatment associated with Lophocampa caryae caterpillar exposures. Three hundred sixty-five exposures to Lophocampa caryae managed by a certified regional poison information center over a 2-year period were analyzed. Pediatric exposures were responsible for 80% of the reports and 92.1% were dermal exposures, 7.5% oral, and 0.4% ocular. Dermal exposures with minimal symptoms were treated at home with the supportive measures of hair and spine removal, irrigation, antihistamine, and/or topical steroid administration. Symptom resolution occurred within 24 hours. Symptomatic patients with oral exposures and positive visualization of hairs or spines, were referred to an emergency department for medical evaluation and removal of the caterpillar hairs. Adult exposure and treatment patterns were similar to the pediatric exposures. Removal of the defensive guard hairs or spines is the primary treatment. Supportive care with irrigation, antihistamines, and/or corticosteroids can decrease the intensity of symptoms.     

Biological effects of natural and recombinant mistletoe lectin and an aqueous mistletoe extract on human monocytes and lymphocytes in vitro

Mistletoe lectin is thought to constitute the active principle in extract preparations from mistletoe, which are widely used as immunomodulators in adjuvant tumor therapy. However, no study exists which compares the immunological potency of different well-defined mistletoe lectin preparations on human immune cells. Therefore, in the present study the biological effects of an aqueous mistletoe extract, standardized for mistletoe lectin I (eML), the isolated natural mistletoe lectin (nML), and the recombinant form of this lectin (rML) on human peripheral blood monocytes and lymphocytes were compared with respect to cell viability and cytokine induction. After 48-hr incubation of peripheral blood mononuclear cells (PBMC) with rML, nML, and eML, a continuous concentration-dependent decrease in cell viability was found with an IC50 of about 3 ng/ml for rML and nML and 10 ng/ml for eML, respectively. This effect also was seen when isolated lymphocytes and monocytes were separately incubated with the lectin preparations. After incubation of PBMC and isolated monocytes of 5/10 blood donors with eML, an increase in cell viability was found at lectin concentrations between 10 and 1,000 pg/ml. This effect was not seen with the pure lectin preparations nML and rML. After 48-hr incubation of PBMC with rML, nML, and eML, induction of IL-1-beta, TNF-alpha, IL-2, IL-6, and IL-10 but not IFN-gamma was measured. For IL-1-beta it could be shown that cytokine induction took place at a broad lectin concentration range (0.1-100 ng/ml). Cytokine levels varied greatly in the PBMC cultures of the different blood donors. When monocytes were separately incubated with eML, nML, and rML for 48 hr, high levels of IL-1-beta were found. In contrast, in cultures of separated lymphocytes from the same donors only a minimal production of IL-1-beta and no production of IFN-gamma was found after incubation with rML, nML, and eML. It is concluded that there are quantitative differences in the immunomodulatory effects of the mistletoe lectin preparations on human monocytes and lymphocytes. Therefore, measurement of cell viability and cytokine induction may be a diagnostic laboratory tool to determine the immunological potency of various mistletoe preparations and may help to clarify the clinical benefit of therapies with these substances.     

Patients are talking about ... Iscador (mistletoe)

Mistletoe generally is categorized as American mistletoe or European mistletoe. Despite its well-known potential for toxicity, mistletoe continues to be used as an herbal remedy and recently has received a great deal of media attention. The U.S. Food and Drug Administration classified mistletoe as a food additive that cannot be marketed unless proven safe for consumption (DerMarderosian, 1992). Several components of the plant have been found to possess antineoplastic activity and warrant further investigation for their clinical potential. At this time, however, mistletoe as a single-agent therapy has not been scientifically validated in the treatment of breast cancer.     

Evaluating exposures to plants

Most clinical problems due to plant exposures result from experimentation with or overt abuse of plant parts and extracts. Plant exposures may present as complex pharmacologic problems that challenge the diagnostic and therapeutic skills of the physician. Although specific physiologic antagonists (antidotes) may exist for specific intoxications, basic decontamination and supportive techniques are often all that may be offered.     

Plant exposures: wilderness medicine

This article discusses poisonous plants, the symptoms that might arise if they are ingested, and the treatments that should be administered to patients.     

Subcutaneous infiltrates induced by injection of mistletoe extracts (Iscador)

Iscador, an aqueous extract of Viscum album L., has been widely used as an anti-cancer drug for several decades. Mistletoe lectins have the capacity to activate nonspecific defense mechanisms, and lectin-carbohydrate interactions may be involved in clinically applicable immunomodulation. During treatment with whole-plant mistletoe extract, an inflammatory reaction usually occurs at the site of the injection, early in therapy. These injection sites were examined histologically. Seven subjects received three subcutaneous injections of Iscador QuFrF or Iscador Qu Spezial (twice 0.1 mg and once 2.5 mg) during 9 days. In all subjects, examination of skin biopsies showed a normal epidermis. The dermal and subcutaneous regions contained a dense perivascular lymphocyte infiltrate and increased monocytes. We could not document any increase of plasma cells, eosinophils, mast cells, neutrophils, or granulocytes, as would be the case for a granulomatous infiltrate. In the blood, we observed a significant increase in neutrophils and monocytes 24 hours after administration of 2.5 mg of Iscador.     

Toxicity of a standardized mistletoe extract in immunocompromised and healthy individuals.

Iscador is being used by many patients as unconventional anticancer and immunomodulating therapy. To determine the toxicity profile and biochemical effects of Iscador Qu Spezial (Weleda AG Schw?bisch Gmünd, Germany) in human immunodeficiency virus (HIV)-positive patients and healthy controls, we performed a phase I/II study. Escalating doses of Iscador Qu Spezial, standardized for its lectin and viscotoxin content, were administered to 16 HIV-positive patients and 8 healthy subjects during a period of 6 to 8 months. Iscador Qu Spezial preparations were administered twice per week subcutaneously in increasing doses (ie, 0.01 mg, 0.1 mg, 1.0 mg, 2.0 mg, 5.0 mg, and 0.1 mg/kg for 2-6 weeks per dose). Drug-related adverse effects were flulike symptoms, gingivitis, fever, local erythema, and eosinophilia. These side effects were never severe. The incidence of systemic adverse events was highest in HIV-positive patients. Furthermore, increased urea levels and slightly decreased total protein caused by a minor decrease in albumin were observed. None of the HIV-positive patients progressed in disease stage. Iscador Qu Spezial can be administered safely to immunocompromised patients.