Jellyfish Sting Newsletters: Number 35 - July 2006
Corkeron M, Pereira P, Makrocanis C. Early experience with magnesium administration in Irukandji syndrome.
The administration of magnesium sulphate is a proposed novel therapy for Irukandji syndrome. In this non-randomized, unblinded case series, data from ten patients who received magnesium salts are reviewed. Magnesium sulphate boluses of 10 to 20 mmol, in the six patients for which there was adequate data, reduced pain scores immediately after administration from 8.7+/-1.5 to 2.8+/-2.8 (Wilcoxon rank-sum test, P=0.03). In ten patients blood pressure decreased with a mean difference of -18 mmHg in mean arterial pressure. Magnesium requirements in individual patients varied markedly. Pain on injection occurred in four patients, three of whom had received peripherally administered magnesium chloride, and one patient reported transient ptosis after administration of magnesium sulphate 166 mmol over 18 hours in the setting of severe Irukandji syndrome. Magnesium sulphate administration appears to attenuate pain and hypertension in Irukandji syndrome and warrants further evaluation in this setting.
It appears that MgSO4 is helpful in some, but not all, patients. It gives us a clue but more agents are needed.
Pommier P, Coulange M, De Haro L. Envenimation systémique par méduse en Guadeloupe: Irukandji-like syndrome?
The Irukandji syndrome is a set of severe systemic symptoms observed after envenomation by some tropical jellyfish. The syndrome was first described in Northern Australia where Carukia barnesi was identified as the offending species. A recent report from Florida described three Irukandji-like syndromes in the Caribbean area. The purpose of this report is to describe a similar case involving a healthy young man who developed systemic symptoms after being stung by an unidentified jellyfish in Guadeloupe (French West Indies). These case reports suggest that jellyfish envenomation may not be unusual in the Caribbean.
This paper shows that Irunkandji syndrome has appeared in Guadeloupe as well as Key West in the Atlantic. There is another case in Northern Cuba (Correspondence #9-this Newsletter, January 2006).
Loten C, Stokes B, Worsley D, Seymour JE, Jiang S, Isbister GK. A randomised controlled trial of hot water (45°C) immersion versus ice packs for pain relief in bluebottle stings.
This report corroborates previous data from Hawaii. There are some practical problems. Temperatures of 45°C are difficult to provide and maintain as well as insure that the patient will not experience local pain, a rise in core temperature and the possibility for venom entry to the body because of local vasodilatation. All this needs to be solved.
Boulware DR. A randomized, controlled field trial for the prevention of jellyfish stings with a topical sting inhibitor. J Travel Med. 2006, 13(3):166-171.
Work on jellyfish sting inhibitors continues-see Correspondence #1. This study is controlled and in the field-both good features. The weakness is that we don’t know what the offending animal was nor who (qualifications) made the diagnosis. These need to be reported in a swarm of one species of jellyfish.
A second criticism is that they used their subjects multiple times rather than a new patient with each new trial.
Garm A, Ekstrom P, Boudes M, Nilsson DE. Rhopalia are integrated parts of the central nervous system in box jellyfish. Cell & Tissue Research 2006, March 24.
In cubomedusae, the central nervous system (CNS) is found both in the bell (the ring nerve) and in the four eye-bearing sensory structures (the rhopalia). The ring nerve and the rhopalia are connected via the rhopalial stalks and examination of the structure of the rhopalial stalks therefore becomes important when trying to comprehend visual processing. In the present study, the rhopalial stalk of the cobumedusae Tripedalia cystophora has been examined by light microscopy, transmission electron microscopy, and electrophysiology. A major part of the ring nerve is shown to continue into the stalk and to contact the rhopalial stalk has failed to show any clustering, which indicates that integration of the visual input is probably spread throughout the CNS. Together, the results indicate that cubomedusae have one coherent CNS including the rhopalia. Additionally, a novel gastrodermal nerve has been found in the stalk; this nerve is not involved in visual processing but is likely to be mechanosensory and part of a proprioceptory system.
Lewis C, Long TAF. Courtship and reproduction in Carybdea sivickisi (Cnidaria: Cubozoa). Marine Biology 2005, 147: 477-483.
Courtship and fertilization events in cubozoans have received little attention from biologists, and much of what we know about these processes is based on conjecture or scant anecdotal evidence. The author describes these processes in the cubozoan Carybdea sivickisi by observing mature medusae in vitro. Mature adults engage in courtship during which spermatophores are transferred from the male to the female, who then inserts the gametes into her manubrium. Females accepted multiple spermatophores from multiple males, and only produced one embryo strand. This study also provides evidence that the presence of conspicuous velar spots on the female’s bell margin is a signal of sexual maturity, and that sexual maturity was not reached in either sex until individuals had a bell diameter of a least 5 mm.
Gershwin L. Comments on Chiropsalmus (Cnidaria: Cubozoa: Chirodropide): a Preliminary revision of the Chiropsalmidae, with descriptions of two new genera and two new species.
The nomenclature and identity of Chiropsalmus quadrigatus have been extensively confused. Originally described from Rangoon, Burma, based on an immature and badly damaged specimen, subsequent Philippine and Australian redescriptions do not match primary characters of the holotype. This has led to widespread messiness in identification and classification of this and related species. In order to clarify the nomenclature of the Chiropsalmus-type cubomedusae, a preliminary revision of the Chiropsalmiade is given. Chiropsoides quadrigatus comb. nov. is proposed, in order to reflect the close relationship of this taxon with Chiropsoides buitendijki, based on the shared character of linear-branching pedalia. A common Australian form, often attributed to Chiropsalmus quadrigatus, is herein described as a new genus and species, Chiropsella bronzie. This new form differs from other Chirodropida in having sessile, solid, smooth gastric saccules, wherease in other Chirodropdia these structures are pendant whether they are smooth or branched. This new species is not dangerous to humans. Another form, Chiropsalmus alipes n. sp., is described from the Pacific coast of southern Mexico; this new species differs from others in having long, blade-like pedalia similar to those of the Carybdeida, only four tentacles at maturity per pedalium, each branching in a different direction, and a warty body; comments are made regarding its apparent relationship to the enigmatic Chiropsalmus zygonema. The recently described Chiropsalmus maculatus is moved to a new genus, Chirodectes in the family Chirodropidae.
Peter Fenner transfers the information that a Frenchman from New Caledonia, Eric Mitron, is working in an African tree oil preparation serving as a repellant for Chironex stings.