David Fegan

Conus geographus envenomation

Human envenomation by the aquatic snail genus Conus is an infrequent but potentially fatal injury amongst divers and shell collectors in the Indian and Pacific Oceans. As with other causes of neurotoxic envenomation such as Elapid snakebites, the onset of paralysis may be rapid. Death occurring within 1 h of injury has been reported. Prompt diagnosis and resuscitation, including airway protection and respiratory support, if necessary, may be lifesaving. We describe a non-fatal case of envenomation due to Conus geographus treated at Honiara Central Hospital, Solomon Islands. A 24-year-old male nurse was admitted with a 12-h history of progressive generalised weakness and poor coordination. The previous night, while collecting seashells, he had suddenly felt a mild stinging sensation in his right hand. His systemic symptoms began about 30 min after this local injury. On examination he had a small puncture wound on the middle finger of his right hand, without erythema or swelling. He was dysarthric, had bilateral ptosis, and an absent gag reflex. All peripheral muscle groups were weak, and his coordination was impaired without cerebellar features. His peak expiratory flow rate was 290 L/min (predicted 600 L/min). The remainder of his physical examination was normal. The shell responsible for the injury was recovered by his relatives (figure). He was admitted for observation and a portable pulse oximeter was used to monitor the adequacy of his ventilation. His oxygen saturation remained above 95% on room air. 12 h after admission he developed acute urinary retention for which he required catheterisation. Although weak, he could walk unaided after 48 h. He was discharged after 72 h at which time his physical examination was normal. When reviewed at medical outpatients a month later he had no complaints. Recorded stings by cone shells are rare. Before 1980, 16 fatalities had been recorded, 12 of which were due to C geographus. It is estimated that one quarter of all stings from this species may prove fatal. Two other species, C textile and C marmoreus, have also been reported to kill human beings, although the plausibility of these reports has been questioned on the basis of venom studies on dissected shells. Nocturnally active, carnivorous cone shells are widely distributed in tropical and subtropical waters. They are often found in shallow waters under rocks, along reefs and crawling on sand. Most human stings occur when a collector attempts to clean a freshly-caught shell, or to place it in his or her pocket. The venom is injected into the shell’s natural prey or its human victim through a harpoon-like tooth or radula. The active components, conotoxins, are predominantly polypeptides of less than 30 aminoacids. Their paralytic actions include postsynaptic blockade of the acetylcholine receptor, as well as inhibition of motor endplate depolarisation by sodium-ion channel blockade. Presynaptically, other conotoxins inhibit acetylcholine release by blockade of voltage-gated calcium ion channels. Non-paralytic toxins also exist but their actions, if any, are unknown. Despite efforts to develop an antivenom, there is no specific treatment for cone-shell poisoning and management is essentially supportive. Paralysis, when it occurs, is generally reversible within 24 h, so mechanical ventilation may be justifiable in even the most basic health-care settings. A survey of health workers at our National Referral Hospital revealed little knowledge of this condition. Our patient was a registered nurse who had lived by the sea all his life and supplemented his income by collecting shells, yet he was unaware of the dangers involved. The most likely explanation for such widespread lack of awareness is the rarity of serious envenomation. However, mild cases may go unrecognised or unreported, and fatalities may be misattributed to drowning.`

Resurgence of yaws in Tanna, Vanuatu: time for a new approach?

Recent reports from the island of Tanna in Vanuatu suggest that yaws has resurged. We carried out a serological and clinical survey to determine the prevalence and clinical presentation of yaws on the island. A total of 306 random serum samples were tested for rapid plasma reagin and rapid diagnostic determine syphilis: 31.04% were positive for one or both tests; 39.8% of children surveyed in three schools had skin lesions consistent with yaws; and there were only two cases of secondary yaws osteitis and no cases of tertiary yaws. These results confirm that the disease has resurged but appears to be attenuated. Intramuscular benzathine penicillin is the currently recommended treatment for yaws. We suggest that a stat dose of oral azithromycin would be a more accessible treatment as it could be prescribed by village health workers and therefore enable yaws control to be more easily incorporated into other primary health-care programmes.

Attitude towards family planning in Dharan, east Nepal: implications for the family planning programme

A survey of the knowledge, attitude and practice of family planning was conducted in Dharan, Nepal. The town offers a full range of family planning services free of charge. There was a strong desire to limit family size; 52.5% of couples were currently using some modern method of family planning. Of the current users, 62.3% had been sterilized, including 92.3% of those in the lowest socioeconomic group. Health risks and incompleteness of the family were the most common reasons for non-use of contraception, the latter reason reflecting ignorance of the temporary nature of some methods. There was a strong preference for male children and couples rarely used contraception until at least one so had been born. Even in this prosperous town where couples were highly motivated towards family planning and all methods were readily available, there was heavy reliance on sterilization. This is typical of Nepal and has largely been responsible for the failure of the family planning programme--as most couples choosing sterilization are in the older age group and have completed a relatively large family. If Nepal is to succeed in meeting its target of reducing the total fertility rate (i.e., births per woman) from the current 5.8 to 4 by the year 2000 it will need not only to expand services but actively to promote temporary methods of contraception, particularly the more reliable longer acting reversible methods such as Depo-Provera, Norplant and intrauterine contraceptive devices.

SLE and dental erosion: a lethal cocktail

A 13-year-old Pacific Island girl presented complaining of fever, joint pain and dry mouth. She was using limes to relieve her dry mouth. On examination, the most striking clinical finding was severe dental erosion and caries. Autoimmune serology confirmed a diagnosis of systemic lupus erythematosus (SLE) with possible Sjögren’s syndrome. The case illustrates the devastating consequence of excessive consumption of acidic citrus juice in sicca syndrome.

Obesity – More than non‐communicable diseases

Obesity is increasing in both developed and developing countries. Recent reports suggest that rates of obesity in Pacific Island countries rank among the highest in the world. The direct association between obesity and non-communicable diseases (NCD) is well known. The cost of obesity-associated NCDs in Tonga is estimated to be 60% of health budget and 39% in Fiji. However, other problems associated with obesity are less well documented.

Use of steroids in dermatological emergencies.

INTRODUCTION Physicians in the tropics are particularly slow to use high dose steroids. This is justified because of their well known associated morbidity in environments where parasitic disease and tuberculosis are common. There are certain dermatological emergencies which are not uncommon in the tropics in which early high dose steroids are the cornerstone of treatment. To illustrate this point we present four such cases seen in our hospital over the last 6 months.