Never eat an ugly fish: three cases of tetrodotoxin poisoning from Western Australia

Tetrodotoxin is a powerful axonal blocking agent found in a number of marine creatures, including puffer fish. Fatal and near fatal poisonings due to puffer fish ingestion have been described in the medical literature, but few reports are from Australia. Three adults from the same family (two men aged 40 and 24 years and one woman aged 47 years) presented to the Fremantle Hospital Emergency Department six hours after catching and eating an unknown fish. Two developed typical symptoms of tetrodotoxin poisoning including tongue and lip paraesthesiae, blurred vision, ataxia, vomiting and progressive muscular paralysis with inability to stand. They were admitted to the intensive care unit although neither required mechanical ventilation. The third had minimal signs and was observed in the emergency medicine observation ward overnight. All were discharged the next day with some residual ataxia. Clinically significant tetrodotoxin poisoning may culminate in respiratory failure and death if untreated. There is no specific antidote and treatment is supportive. The literature on this unusual poisoning is reviewed.     

Regulation of human B cell activation by prostaglandin E2. Suppression of the generation of immunoglobulin-secreting cells.

The role of prostaglandin E2 (PGE2) in the generation of immunoglobulin-secreting cells (ISC) from human peripheral blood B cells was examined. Initial studies demonstrated that monocyte (M phi)-mediated suppression of the generation of ISC in Staphylococcus aureus (SA)-stimulated cultures was mitigated by indomethacin, and thus suggested that the cyclooxygenase pathway products of arachidonic acid played a role in the regulation of B cell activation. The possibility that PGE2, one of the major products of this pathway generated by M phi-affected human B cell responses, was therefore investigated. PGE2 was found to cause concentration-dependent inhibition of the generation of ISC in pokeweed mitogen- or SA-stimulated B cell cultures supported by T cells. Studies were therefore carried out to determine whether PGE2 inhibited the production of necessary T cell factors or directly altered B cell responsiveness. Initially, the effect of PGE2 on the capacity of mitogen-stimulated cells to secrete a factor that supported the differentiation of B cells into ISC was investigated. Excessive numbers of M phi or PGE2 inhibited the production of B cell differentiation factor from mitogen-stimulated T cells. The effect of PGE2 on the capacity of B cells to differentiate into ISC was more complex. PGE2 inhibited the generation of ISC when B cells were stimulated with SA and B cell differentiation factor-containing T cell supernatants. PGE2-mediated inhibition of ISC generation was observed even when addition of PGE2 was delayed until after ISC first were detected in culture. By contrast, PGE2 caused only minimal inhibition of the generation of ISC cultures stimulated by T cell supernatants alone or protein A-free SA and T cell supernatants. These results suggested that SA-responsive B cells were particularly sensitive to inhibition by PGE2. Additional experiments supported the conclusion that B cell sensitivity to inhibition by PGE2 is augmented by the immunoglobulin cross-linking effects of protein A-containing SA. Overall, the results support the conclusion that PGE2 at physiologically relevant concentrations can influence human antibody responses by means of a direct inhibitory action on the responding B cell or an indirect one on the production of necessary T cell factors.     

Acquired immunodeficiency syndrome-associated non-Hodgkin's lymphomas and other malignancies in patients with hemophilia

Non-Hodgkin's lymphoma (NHL) is the most common human immunodeficiency virus (HIV)-associated malignancy in hemophiliacs. We studied the incidence and clinicopathologic features of NHL in 3,041 hemophiliacs followed at 18 US Hemophilia Centers between 1978 and 1989. Of the 1,295 (56.6%) who were HIV(+), 253 (19.5%) developed acquired immunodeficiency syndrome (AIDS), of whom 14 (5.5%) developed NHL. Three NHL occurred in HIV(-) hemophiliacs, for a 36.5-fold greater risk in HIV(+) than HIV(-) hemophiliacs (P < .001). The NHL incidence rate was 29-fold greater than in the US population by Surveillance, Epidemiology, and End Results (SEER) estimates (P < .001). Between 0 and 4 lymphomas have been observed per year between 1978 and 1989. At presentation 13 (92.9%) of the HIV(+) NHL were extranodal. Ten were stage IV, 1 stage II, and 3 stage IE. Ten (71.4%) were high-grade, 3 (21.4%) intermediate-grade, and 1 (7.1%) was a low-grade B-cell lymphoma. Epstein-Barr virus (EBV) DNA was detected in 36% by in situ hybridization, including one central nervous system (CNS) lymphoma. The mean CD4 cell count at NHL diagnosis was 64/mm3, the mean latency from initial HIV infection was estimated to be 59 months, and the median survival was 7 months. The incidence of basal cell carcinoma in HIV(+) hemophiliacs was 18.3-fold greater than in HIV(-) hemophiliacs (P < .001) and 11.4-fold greater than in the US population (P < .001). In conclusion, incidence rates of NHL and basal cell carcinoma in HIV(+) hemophiliacs are significantly increased over rates in HIV(-) hemophiliacs and over rates in the US population. Clinicopathologic presentation of NHL in HIV(+) hemophiliacs is similar to that in HIV(+) homosexual men.     

Therapeutic efficacy of artemether-lumefantrine and artesunate-mefloquine for treatment of uncomplicated Plasmodium falciparum malaria in Luang Namtha Province, Lao People's Democratic Republic

The efficacy of the six-dose regimen of artemether-lumefantrine was compared with the combination of artesunate and mefloquine in a randomised, comparative trial in Luang Namtha Province, Northern Laos. Of 1033 screened patients, 201 were positive for Plasmodium falciparum; 108 patients of all age groups (2-66 years) with acute, uncomplicated P. falciparum malaria were enrolled in the study, 100 of whom were followed-up for 42 days. Fifty-three patients received artemether-lumefantrine and 55 received artesunante-mefloquine. Both drug combinations induced rapid clearance of parasites and malaria symptoms; there was no significant difference in the initial therapeutic response parameters. Both regimes were well tolerated. After 42 days, cure rates were 93.6% (95% CI = 82.5-98.7%; 44 of 47 patients) for artemether-lumefantrine and 100% (95% CI = 93.3-100.0%; 53 of 53 patients) for artesunate-mefloquine. The results show the excellent efficacy and tolerability of both artemether-lumefantrine and artesunate-mefloquine in Northern Laos.     

Australian emergency doctors' and nurses' acceptance and knowledge regarding brain death: a national survey

Healthcare staff's acceptance of brain death (BD) being a valid determination of death is essential for optimized organ and tissue donation (OTD) rates. Recently, resources to increase Australian OTD rates have been aimed at emergency departments (ED) as a significant missed donor potential was discovered. A cross-sectional survey was conducted to assess Australian ED clinicians' acceptance and knowledge regarding BD. Most (86%) of the 599 medical and 212 nursing staff accepted BD, but only 60% passed a 5-item-validated BD knowledge tool. BD knowledge was related to the acceptance of BD. Accepting BD influenced attitudes toward OTD, including willingness to donate. BD acceptance and knowledge were related to education/training regarding OTD, years of experience in EDs, experience with OTD-related tasks, and increased perceived competence and comfort with OTD-related tasks. Of concern, more than half of respondents who did not pass the BD test reported feeling competent and comfortable explaining BD to next of kin; of respondents who had recent experience with this, more than a third failed the BD test. Despite being generally positive toward OTD, Australian ED clinicians do not have a sound knowledge of BD. This may be hampering efforts to increase donation rates from the ED.     

Ideal care and the realities of practice: interdisciplinary relationships in the management of advanced cancer patients in Australian emergency departments

Purpose

Over the course of their illness, a person with cancer is likely to see a number of different healthcare professionals, including those in the emergency department (ED). There is limited research examining the interaction and communication between the involved healthcare professionals when such a patient presents to the ED. This study aimed to explore the views and experiences of interdisciplinary interactions of healthcare professionals caring for patients with advanced cancer who present to the ED.

Methods

Focus groups and semistructured interviews were conducted with clinical staff working in ED, oncology and community and hospital-based palliative care services. Interviews and focus groups were recorded and transcribed verbatim. Thematic analysis was undertaken by three researchers independently. These themes were then discussed by the wider team and consensus reached on themes and subthemes.

Results

Eighty-three healthcare professionals participated in focus groups, and 11 were interviewed. The over-arching theme to emerge was one of a conflict between ideal care and the realities of practice, particularly arising where clinicians from different services were required to work together to provide care. This idea was further understood through a series of subthemes including communication, decision-making and understanding of other services.

Conclusions

Participants articulated agreed upon ideals of optimal care for advanced cancer patients across all three services, however there was frequently discord between these ideals and the actual care provided. Service demands and the day-to-day stressors of practice appeared to influence people’s actions and engender conflict