[Zosteriform cutaneous metastasis in melanoma]. / Mélanome avec métastases cutanées zostériformes.

INTRODUCTION: Cutaneous metastases are common in patients with malignant melanoma. In rare cases, they are distributed on a dermatome, in which case they are known as zosteriform metastases. OBSERVATION: We report the case of a patient with zosteriform metastasis of a malignant melanoma, progressing unfavourably despite surgical excision and immunotherapy. DISCUSSION: The physiopathology of this condition continues to be poorly understood.

Mathematical optimisation of the cisplatin plus etoposide combination for managing extensive-stage small-cell lung cancer patients.

BACKGROUND: Small-cell lung cancer (SCLC) represents one of the most aggressive forms of lung cancer. Despite the fair sensitivity of SCLC to chemotherapy and radiotherapy, the current standard treatment regimens have modest survival rates and are associated with potential life-threatening adverse events. Therefore, research into new optimised regimens that increase drug efficacy while respecting toxicity constraints is of primary importance. METHODS: A PK/PD model for the combination of cisplatin and etoposide to treat extensive-stage SCLC patients was generated. The model takes into consideration both the efficacy of the drugs and their haematological toxicity. Using optimisation techniques, the model can be used to propose new regimens. RESULTS: Three new regimens with varying timing for combining cisplatin and etoposide have been generated that respect haematological toxicity constraints and achieve better or similar tumour regression. The proposed regimens are: (1) Protocol OP1: etoposide 80 mg m-2 over 1 h D1, followed by a long infusion 12 h later (over 3 days) of 160 mg m-2 plus cisplatin 80 mg m-2 over 1 h D1, D1-D1 21 days; (2) Protocol OP2: etoposide 80 mg m-2 over 1 h D1, followed by a long infusion 12 h later (over 4 days) of 300 mg m-2 plus cisplatin 100 mg m-2 over 1 h D1, D1-D1 21 days; and (3) Protocol OP3: etoposide 40 mg m-2 over 1 h, followed by a long infusion 6 h later (3 days) of 105 mg m-2 plus cisplatin 50 mg m-2 over 1 h, D1-D1 14 days. CONCLUSIONS: Mathematical modelling can help optimise the design of new cisplatin plus etoposide regimens for managing extensive-stage SCLC patients.

Anaphylaxis to levofloxacin

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A mathematical model for the administration of temozolomide: comparative analysis of conventional and metronomic chemotherapy regimens.

We propose a mathematical model that takes into account a classical maximum tolerated dose (MTD) chemotherapy regimen (whose primary targets are the tumor cells) as well as a metronomic chemotherapy regimen (whose primary targets are the tumor endothelial cells) for the administration of temozolomide (Temodal(®)) in order to compare the effectiveness of these two types of protocols. The model is built from 4 natural hypotheses: (H1) without treatment the tumor growth follows a Gompertz model, (H2) endothelial cells are more sensitive to temozolomide than cancer cells, (H3) the anti-angiogenic effect blocks tumor growth, and (H4) endothelial cells are more genetically stable than cancer cells and thus less likely to develop resistance to temozolomide. Then, we compared a conventional MTD regimen of 200 mg/m(2) temozolomide J1-J5 every 28 days with a daily metronomic regimen of 85 mg/m(2)/day for cycles of 42 days. Our mathematical model shows that the metronomic regimen induces tumor regression through anti-angiogenic effects while the MTD regimen fails to do so, due to the emergence of temozolomide resistance in cancer cells. Overall, our model is consistent with clinical observations and provides an interesting tool toward the personalization of anticancer treatments, through optimization of dose and schedule of chemotherapy based on individual patient characteristics.

A new model for determining the MTD during phase-I trials in pediatric oncology.

The primary goal of phase I studies in oncology is to determine the MTD (Maximum Tolerated Dose) for a drug. This MTD is determined with respect to an accepted risk (usually 33%) to see a limiting toxity for patients. In this paper we propose a new mathematical model to determine the MTD. An important feature of this model is that the limiting toxicity can be formulated as a combination of several basic graded toxicities such as hematologic or neurological. Another feature is the possibility to take into account several patient covariates to individualize the determination of the MTD. The model is a bayesian model where some prior information has been considered. The model is expected to work better than traditional empirical schemes for determining the MTD because it uses at every step all the available information on patients, and adds some major improvements as compared with existing CRM strategies because it uses whole data made available, including low-grades toxicities. Finally the model has been validated with a retrospective data set on 17 patients from a phase I study on paclitaxel in pediatric oncology. Calculated MTDs for each patient were found to be markedly different than the doses actually given following a traditional dose-escalation methodology. Results suggest that our new model provides a better and safer way to drive dose-escalation in phase-I trials as compared with traditional schemes.

Passive transient transfer of peanut allergy by liver transplantation.

We report a case of transient symptomatic transferred IgE-mediated peanut allergy after elective blood-group compatible liver transplantation. We show that the allergy was transient and therefore passive, authorizing further uneventful peanut consumption. Skin tests with commercial peanut extract and native peanut were performed in the recipient. Circulating specific IgE against peanut and recombinant peanut allergens (rArah1, rArah2, rArah3) was measured in stored serum samples collected from the recipient between 6 months before and 8 months after liver transplantation. Specific IgE levels in the donor were measured at the time of multiorgan donation. In the recipient, diagnosis of IgE-mediated peanut anaphylaxis was based on the clinical history and detection of specific IgE against peanut and recombinant major peanut allergens (rArah1, rArah2 and rArah3). Skin tests were negative and specific IgE undetectable 6 months after the clinical reaction. Oral peanut challenge was negative excluding persistent peanut allergy. This case confirms that IgE-mediated peanut allergy can be transferred by liver transplantation and shows that it may be transient and therefore passively acquired.

Anaphylactic reaction after methylene blue-treated plasma transfusion.

Methylene blue-treated fresh-frozen plasma (MB-FFP) is mainly used in Europe. The advantage of the methylene blue system is that units can be treated individually. The combined action of methylene blue and illumination is a photodynamic process preventing viral RNA and DNA replication. We report the first immediate allergic hypersensitivity reaction to methylene blue-treated plasma transfusion. The clinical course and subsequent assessment of the allergic reaction, including skin tests and basophil activation test, confirmed methylene blue-induced IgE-mediated anaphylaxis. All immediate reactions after MB-FFP transfusion should be investigated to document the underlying mechanism.

[Allergic risk during paediatric anaesthesia]. / Risque allergique en anesthésie pédiatrique.

OBJECTIVES: To propose the different modalities of management of the allergic risk occurring during paediatric anaesthesia. STUDY DESIGN: Literature analysis. METHODS: Literature research using the Medline((R)) database and MeSH format according to keywords, including publications in French and English since 1982. RESULTS: The overall incidence for anaphylactic reactions was estimated at one in 7741 anaesthetic procedures during paediatric anaesthesia. Latex anaphylaxis was mostly involved with an incidence at one in 10,159 anesthetic procedures. The risk factors of latex sensitization are known. Primary latex prophylaxis is efficient in patients at risk of latex sensitization. In contrast to adults, neuromuscular blocking agents (NMBAs) are rarely involved in children, with an incidence at 1 in 81,275 anaesthetic procedures. The Ring and Messmer clinical scale allows quantifying the severity and helps managing the care of immediate hypersensitivity reactions. Clinical symptoms associate cardiovascular, respiratory and cutaneous-mucous signs according to different severity grades. Epinephrine associated to fluid loading, remains the first-line agent in case of severe reactions. The allergological assessment is key to the management of these reactions and is required in order to identify the mechanism of the reaction and the culprit drug or substance involved. CONCLUSIONS: Allergic reactions to NMBAs occurring during paediatric anaesthesia are rare whereas those with latex are more frequent. Therefore, the reduction of the allergic risk during paediatric anaesthesia essentially requires a latex-free environment.

Perioperative anaphylaxis.

The incidence of immune-mediated anaphylaxis during anesthesia ranges from 1 in 10,000 to 1 in 20,000. Neuromuscular blocking agents represent the most frequently involved substances, followed by latex and antibiotics, but every drug or substance used may be involved. Diagnosis relies on tryptase measurements at the time of the reaction and skin tests and specific IgE or basophil activation assays.

[Immediate allergy to iodinated contrast agents and prevention of reactions]. / Allergie immédiate aux produits de contraste iodés et prévention des réactions.

The incidence and morbimortality of immediate hypersensitivity reactions following iodinated contrast media (ICM) injection remain unknown. The diagnosis of an immediate hypersensitivity reaction relies on a triad associating the precise description of the initial clinical manifestations and their delay of onset, the results of the biological assessment performed after the reaction including histamine and tryptase serum level measurements, and the results of skin testing with the culprit agent. Analysis of these data allows identification of the pathophysiologic mechanism of the reaction and the allergen involved in case of allergic hypersensitivity. Skin tests should be performed according to strict criteria. Cross-reactivity with ICM has to be investigated in order to propose a nonreactive ICM for future procedures. Allergic hypersensitivity to a given ICM imposes its definitive avoidance but not the avoidance of all iodinated drugs. The allergenic sequence has not yet been identified but is not the iodine atom itself. Asthma and treatment with beta-blockers are not risk factors of immediate allergic reactions to ICM per se, but may increase their severity. The various published protocols of premedication do not prevent the occurrence of an allergic/anaphylactic reaction to an ICM. The avoidance of the culprit ICM is the only way to prevent further reactions.

[Mastocytosis and anaesthesia]. / Mastocytoses et anesthésie.

Mastocytosis are characterized by an accumulation of abnormal mast cells in various tissues. Their incidence is estimated at 1/150,000 patients. Pure cutaneous mastocytosis which are mainly observed during childhood may resolve spontaneously during adolescence, whereas systemic mastocytosis involving one or more organs or tissues are more observed in adults. The initial event leading to mastocytosis is believed to be related to activating mutations in c-kit receptor, thus resulting in increased proliferation of mast cells precursors, migration in various tissues and degranulation leading to clinical signs. This nosologic entity does not belong to allergic diseases. Their perioperative management involves a multidisciplinary approach. The degranulation of mast cells with subsequent clinical symptoms can be triggered by psychological, chemical, traumatic, physical (rubbing, extreme temperatures...) agents. Avoiding these triggers should be realized whenever possible according to each patient. The premedication has not proven its efficiency. Tryptase measurement is part of the preoperative biological assessment. The clinical signs severity is related to the cardiovascular homeostasis disturbances (arterial hypotension, cardiovascular collapse, cardiac arrest). The cardiovascular symptoms do not correlate to the cutaneous versus systemic description of the disease. The drug of choice for the treatment of the severe cardiovascular signs is epinephrine associated to vascular loading. The aim of this literature review is to suggest the different modalities of perioperative care of patients with mastocytosis.

Hypersensitivity reactions to neuromuscular blocking agents.

Neuromuscular blocking agents are the leading drugs responsible for immediate hypersensitivity reactions during anaesthesia. Most hypersensitivity reactions represent IgE-mediated allergic reactions. Their incidence is estimated to be between 1 in 3,000 to 1 in 110,000 general anaesthetics. However striking variations have been reported among countries. The mechanism of sensitisation seems to implicate the presence of a substituted ammonium ion in the molecule. Due to lack of exposure prior to the reaction in a large number of reactors, it has been hypothesised that sensitisation may involve other, as yet undefined, substituted (quaternary and tertiary) ammonium ion containing compounds such as pholcodine, present in the environment of the patient. This hypothesis is still under investigation. The mechanism of non-IgE mediated hypersensitivity reactions is less well known. Identified mechanisms correspond to direct histamine release or interactions with muscarinic and nicotinic receptors. Allergic reactions cannot be clinically distinguished from non-IgE-mediated reactions. Therefore, any suspected hypersensitivity reaction must be investigated using combined pre and postoperative testing. Because of the frequent but not systematic cross-reactivity observed with muscle relaxants, every available neuromuscular blocking agent should be tested, using intradermal tests to confirm the responsibility of the suspected drug which should be definitely excluded. Cross-sensitivity investigation will also try to identify the safety of drugs that can be potentially used in future anaesthesia. The determination of basophil activation investigations using direct leukocyte histamine release test or flow cytometry would be of particular interest to investigate cross sensitisation in complement to skin tests. There is no demonstrated evidence supporting systematic pre-operative screening in the general population at this time. However, since no specific treatment has been shown to reliably prevent anaphylaxis, allergy assessment must be performed in all high-risk patients. In view of the relative complexity of allergy investigation, and of the differences between countries, an active policy to identify patients at risk and to provide any necessary support from expert advice to anaesthetists and allergologists through the constitution of allergo-anaesthesia centres in every country should be promoted.

Anaesthetists should be aware of delayed hypersensitivity to phenylephrine.

Delayed reactions to phenylephrine, used as a mydriatic agent during ophthalmological surgical procedures, are well known. We diagnosed a delayed hypersensitivity reaction to phenylephrine included in an ophthalmic insert in a woman presenting, 24 h after surgery, with an acute blepharoconjunctivitis associated with eyelid eczema of the operated eye. The diagnosis was supported by the recognition of clinical symptoms associated with a positive patch test to phenylephrine. Patients who present with previous contact eczema to phenylephrine may develop a generalized eczema if phenylephrine is injected intravenously. Intravenous phenylephrine is increasingly being used in the operating room to treat hypotension. This case report confirms the need for systematic allergological investigation of all drugs and substances administered during the peri-operative period in order to avoid a delayed hypersensitivity reaction occurring after the peri-operative period. Anaesthetists should be aware of the possibility of delayed hypersensitivity reactions involving phenylephrine.

[Treatment of anaphylactic reaction in pre-hospital and in the emergency room: literature review]. / Prise en charge d'une réaction anaphylactique en extrahospitalier et aux urgences: revue de la littérature.

Care and therapy of patients experiencing an anaphylactic reaction should be known by the physicians working in the emergency medical unit or in pre-hospital care. The epidemiology of these reactions varies according to the countries. The main aetiologies are due to food, hymenoptera or drugs. The clinical scale proposed by Ring and Messmer aims to classify the reactions in 4 grades according to their severity and is useful to stratify therapy. According to the grade of the reaction, the drug of choice for the treatment of anaphylaxis is epinephrine associated to vascular expansion. Anaphylaxis during pregnancy is described. Patients who experienced an immediate hypersensitivity reaction should undergo an allergological investigation to prove the immune mechanism and to identify the culprit allergen. Reporting to the Drug Safety Monitoring Authorities when a drug is implicated should not be forgotten.

Anaphylactic reaction to patent blue V after sentinel lymph node biopsy.

BACKGROUND: We report a documented grade III IgE-mediated hypersensitivity reaction associated with the use of 2.5% patent blue V dye for sentinel lymph node biopsy during breast cancer surgery. METHODS: Immediately after the reaction, when hemodynamic stability was obtained, plasma histamine was measured whereas serum tryptase was not. Six weeks later, with the patient's consent, cutaneous tests to patent blue V dye, methylene blue dye, latex and all drugs used during surgery were performed according to standardized procedures. RESULTS AND CONCLUSION: Clinical symptoms, biological assessment results and cutaneous tests positivity confirmed the onset of an anaphylactic reaction due to patent blue V. Of interest, the positivity of the cutaneous tests observed with patent blue V was not found with methylene blue which might be proposed for further investigations in our patient. This case report confirms the need for systematic allergological investigation of all drugs and substances administered during the peri-operative period in case of an immediate hypersensitivity reaction occurring during anesthesia.