Recreational and occupational field exposure to freshwater cyanobacteria – a review of anecdotal and case reports, epidemiological studies and the challenges for epidemiologic assessment

Cyanobacteria are common inhabitants of freshwater lakes and reservoirs throughout the world. Under favourable conditions, certain cyanobacteria can dominate the phytoplankton within a waterbody and form nuisance blooms. Case reports and anecdotal references dating from 1949 describe a range of illnesses associated with recreational exposure to cyanobacteria: hay fever-like symptoms, pruritic skin rashes and gastro-intestinal symptoms are most frequently reported. Some papers give convincing descriptions of allergic reactions while others describe more serious acute illnesses, with symptoms such as severe headache, pneumonia, fever, myalgia, vertigo and blistering in the mouth. A coroner in the United States found that a teenage boy died as a result of accidentally ingesting a neurotoxic cyanotoxin from a golf course pond. This death is the first recorded human fatality attributed to recreational exposure to cyanobacteria, although uncertainties surround the forensic identification of the suspected cyanotoxin in this case. We systematically reviewed the literature on recreational exposure to freshwater cyanobacteria. Epidemiological data are limited, with six studies conducted since 1990. Statistically significant increases in symptoms were reported in individuals exposed to cyanobacteria compared to unexposed counterparts in two Australian cohort studies, though minor morbidity appeared to be the main finding. The four other small studies (three from the UK, one Australian) did not report any significant association. However, the potential for serious injury or death remains, as freshwater cyanobacteria under bloom conditions are capable of producing potent toxins that cause specific and severe dysfunction to hepatic or central nervous systems. The exposure route for these toxins is oral, from ingestion of recreational water, and possibly by inhalation. A range of freshwater microbial agents may cause acute conditions that present with features that resemble illnesses attributed to contact with cyanobacteria and, conversely, acute illness resulting from exposure to cyanobacteria or cyanotoxins in recreational waters could be misdiagnosed. Accurately assessing exposure to cyanobacteria in recreational waters is difficult and unreliable at present, as specific biomarkers are unavailable. However, diagnosis of cyanobacteria-related illness should be considered for individuals presenting with acute illness following freshwater contact if a description is given of a waterbody visibly affected by planktonic mass development

Simpatectomia cervicotoracica por videotoracoscopia: experiência inicial

O objetivo do presente trabalho é avaliar os resultados iniciais obtidos com a simpatectomia cervicotorácica videotoracoscópica. De outubro de 1995 a outubro de 1997 foram realizados 24 procedimentos em 14 pacientes: dez homens e quatro mulheres, com idades que variaram de 16 a 56 anos, média de 30 anos. Indicações para a operação foram: hiperidrose palmar em dez pacientes, isquemia de mão em três e causalgia em um. Nos casos de hiperidrose, a ressecção da cadeia simpática incluiu T2 e T3. Nos portadores de isquemia e causalgia também o gânglio estrelado foi ressecado. Vinte e três das 24 extremidades mostraram excelente resposta imediata à simpatectomia. Somente uma extremidade de paciente com hiperidrose permaneceu inalterada devido a procedimento incompleto, tendo sido desnervada pela mesma técnica em reoperação posterior, com bom resultado. Pneumotórax residual pós-operatório ocorreu em uma paciente com resolução espontânea. Treze pacientes tiveram seguimento que variou de dois a 18 meses, com média de 11 meses. Não houve mortalidade nessa série, e a principal complicação tardia observada nos pacientes operados por hiperidrose foi a hiperidrose compensatória, que ocorreu, em grau variado, nos nove pacientes com seguimento, sendo que em 30% deles esta manifestação foi significativa. Concluímos tratar-se de procedimento simples, seguro, eficiente e de melhor aceitação por parte dos pacientes do que a operação convencional

The treatment of spasticity with Delta9-tetrahydrocannabinol in persons with spinal cord injury

STUDY DESIGN: Open label study to determine drug dose for a randomized double-blind placebo-controlled parallel study. OBJECTIVES: To assess the efficacy and side effects of oral Delta(9)-tetrahydrocannabinol (THC) and rectal THC-hemisuccinate (THC-HS) in SCI patients. SETTING: REHAB Basel, Switzerland. METHOD: Twenty-five patients with SCI were included in this three-phase study with individual dose adjustment, each consisting of 6 weeks. Twenty-two participants received oral THC open label starting with a single dose of 10 mg (Phase 1, completed by 15 patients). Eight subjects received rectal THC-HS (Phase 2, completed by seven patients). In Phase 3, six patients were treated with oral THC and seven with placebo. Major outcome parameters were the spasticity sum score (SSS) using the Modified Ashworth Scale (MAS) and self-ratings of spasticity. RESULTS: Mean daily doses were 31 mg with THC and 43 mg with THC-HS. Mean SSS for THC decreased significantly from 16.72 (+/-7.60) at baseline to 8.92 (+/-7.14) on day 43. Similar improvement was seen with THC-HS. We observed a significant improvement of SSS with active drug (P=0.001) in the seven subjects who received oral THC in Phase 1 and placebo in Phase 3. Major reasons for drop out were increase of pain and psychological side effects. CONCLUSION: THC is an effective and safe drug in the treatment of spasticity. At least 15-20 mg per day were needed to achieve a therapeutic effect