Clinical Flowchart

Anaphylactic reactions, in particular anaphylactic shock, may be difficult to distinguish in differential diagnostic terms from systemic toxic effects.
E.g., Tibbals (2006) comments: “A case of rapid collapse (unconsciousness, pulselessness and unreactive dilated pupils) after a sting by P. utriculus has been considered circumstantially an allergic phenomenon (Golan 1968)”. “In another case, features of immediate hypersensitivity (urticaria, oedma and bronchospasm) responded quickly to treatment with epinephrine, volume expansion and steroids but one week later a pruritic vesicular eruption occurred on skin initially stung” (Edwards and Edwards 2000). 

Autonomic neuromuskular nervous system effects: Clinical features of the syndrome resemble those of an adrenal medullary or catecholamine excess, such as seen in cases of phaeochromocytoma. 

Other species carybdeid jellyfish that may cause Irukandji syndrome (Gershwin et al 2013: “Table 1.2 Summary of ecology and syndrome characteristics of species known or believed to cause Irukandji syndrome”; Tibballs et al 2012; Debate: Little et al 2006, Gershwin 2006, Fenner 2006):
Alatina mordens, Carukia shinju, Carybdea alata, Carybdea rastonii, Carybdea xaymacana, Malo maxima, Malo kingi, Alatina mordens, Gerongia rifkinae, and Morbakka fenneri.

• Signs and symptoms appearing with a delay of 5 to 120 minutes (average 25 to 40 minutes).
• These symptoms of envenoming can persist for up to 24 h to 72 h or more.

Irukandji‑associated muscle pain and cramps result from combined autonomic (catecholamine‑mediated), neurotoxic (ion‑channel mediated), and possibly direct muscular and inflammatory mechanisms, rather than a single isolated pathway” (Winkel et al 2005)