A Case Report of Sodium Hypochlorite Accident

Sodium hypochlorite is widely used as an irrigating solution in dental practice. Despite its safe properties, serious complications can result from inadvertent use. We report a patient presenting to the accident and emergency department for sodium hypochlorite accident during dental root canal therapy. The management of this dental emergency condition is discussed.

Two Cases of Chloral Hydrate Overdose

Chloral hydrate overdose is associated with cardiac toxicities, gastrointestinal tract injuries, central nervous system and respiratory depression. Among all the complications, cardiac arrhythmias are particularly concerning and frequently reported in the literature. The majorities of fatalities from chloral hydrate overdose are due to refractory cardiac arrhythmia. Chloral hydrate-induced arrhythmias are resistant to most of the standard anti-arrhythmic agents but have good response to propranolol. We report two cases of severe chloral hydrate overdose presenting with alarming cardiac rhythm disturbances. One of the patients was successfully treated with intravenous propranolol in the accident and emergency department. The management of chloral hydrate overdose in particular to its cardiac toxicity is reviewed.

Ophthalmic Injuries from a Spitting Chinese Cobra

A man sustained conjunctivitis of the left eye after being spat by the venom of a Chinese cobra (Naja atra). He received fluid irrigation, topical antibiotic and topical steroid treatment. The conjunctivitis resolved without sequalae after 4 days. Various treatment options are discussed.

Three Cases of Peripartum Cardiomyopathy

Dyspnoea and dizziness are very common presentations in the emergency department. We describe three female patients complaining of dyspnoea and dizziness during their postpartum period. Clinical manifestations and diagnosis of peripartum cardiomyopathy is discussed.

Two Cases of the Purple Urine Bag Syndrome

The purple urine bag syndrome, purple discoloration of urine, is an uncommon and alarming condition in patients requiring long-term urinary catheterization but the clinical course is usually benign. We report two cases of the syndrome with a literature review on its aetiology and management.

A Case Report of Ocular Injury by Euphorbia Plant Sap

Ocular injuries in the working place are usually related to exposure to industrial chemical substances e.g. acid and alkaline, radiation energy e.g. ultra-violet light or even direct trauma. Ocular injuries by saps of plants are uncommon but can result in serious ocular complications. We report a case of ocular injury of a gardener caused by the sap of a Euphorbia plant, Euphorbia trigona. The ocular complications and management of Euphorbia plant sap-associated eye injuries are reviewed.

An Uncommon Cause of Deep Vein Thrombosis: Mycotic Aneurysm Secondary to Salmonella Arteritis

Mycotic aneurysm is an uncommon surgical emergency with high mortality. Endovascular infection due to salmonella is the commonest cause of intra-abdominal mycotic aneurysm. We report a rare presentation of mycotic aneurysm in a 78-year-old man who presented to the accident and emergency department with deep vein thrombosis due to compression of the iliac vein by a mycotic aneurysm arising from the internal iliac artery and an adjacent abscess. A comprehensive review of the aetiology, clinical presentation and management of mycotic aneurysm secondary to salmonella arteritis is presented.

Local antivenom treatment for ophthalmic injuries caused by a Naja atra

We report a case of local antivenom therapy for ocular exposure to the venom of Naja atra. An 83-year-old woman sustained conjunctival and corneal injuries by the venom of a spitting N. atra. Local instillation of N. naja antivenom quickly relieved the pain as measured by visual analog scale, and she recovered uneventfully. Good recovery ensuing topical antivenom administration for ocular exposure to the venom of spitting N. atra and Naja nigricollis has been described in literature, but the pain response was not thoroughly documented. The mechanism of antivenom for pain relief remains to be established. In light of the associated positive outcome observed in human, the role of ocular antivenom therapy merits further study.

A cross-sectional survey of snake oral bacterial flora from Hong Kong, SAR, China

OBJECTIVE

To determine the pattern of oral bacterial flora and their sensitivity to antibiotics in freshly captured native snakes in Hong Kong SAR, People's Republic of China.

METHODS

Healthy native snakes were captured and kept in a designated centre. Snake species were identified by experienced herpetologists. Mouth swabs were taken by the veterinarian using strict aseptic techniques. The snakes were released back to the wild immediately after the above procedure. Swabs were sent for microbiological studies of bacterial culture and antibiotic sensitivity.

RESULTS

47 venomous snakes of the families Colubridae, Elapidae and Viperidae and 53 non-medically important snakes were captured. 406 bacterial isolates of 72 different species were cultured: these included gram negative and positive bacterial species and also anaerobic bacterial species. With the exception of the white-lipped pit viper (Cryptelytrops albolabris), venomous snakes harboured more pathogenic bacteria and total bacteria species compared to the non-medically important species. Of the venomous snakes, the Chinese cobra (Naja atra) harboured the largest number of bacterial species. In the present study, all gram negative bacteria associated with wound infection were sensitive to levofloxacin, netilmicin and piperacillin/tazobactam. Many gram negative bacteria in the study were not sensitive to cefuroxime axetil. Amoxicillin/clavulanic acid was an appropriate choice to cover Enterococcus faecalis and anaerobes.

CONCLUSION

In the presence of wound infection from snakebite injury in Hong Kong, first line empirical antibiotics include amoxicillin/clavulanic acid plus levofloxacin. Prophylactic antibiotics may be considered in selected cases of Chinese cobra (N. atra) bite, otherwise prophylactic antibiotics are not recommended in snakebite unless tissue necrosis is present.

An Unusual Cause of Delirium in a Psychiatric Patient: Abrupt Clozapine Discontinuation

Rapid clinical deteriorations have been reported after abrupt discontinuation of clozapine. A 42-year-old psychiatric patient presented with ingestion of hand-disinfectant solutions causing transient impairment of his conscious level. His clozapine therapy was discontinued for a short period of time and he developed delirium with normal results of investigations for underlying organic causes. His delirium resolved rapidly after the reintroduction of clozapine. The withdrawal effects of abrupt discontinuation of clozapine are discussed in this article.

Five-year experience with Chinese cobra (Naja atra)--related injuries in two acute hospitals in Hong Kong

OBJECTIVE

To review the clinical features and management of patients with injuries related to the Chinese cobra (Naja atra).

DESIGN

Retrospective study.

SETTING

Two acute hospitals in Hong Kong.

MAIN OUTCOME MEASURES

The nature of injuries, envenoming features, complications, response to antivenom therapy, and outcome.

RESULTS

Eighteen patients were recruited during the 5-year study period. Fifteen of them were snake-bitten, the remaining three suffered ocular injuries. Of the 15 patients with cobra bites, 14 (93%) presented with local swelling. No patient developed severe neurotoxic symptoms. Two patients had laboratory features of haemolysis. Fourteen patients received antivenom therapy and five of them subsequently underwent surgical interventions for extensive local tissue damage and necrosis. There was no fatality.

CONCLUSION

Bites from Chinese cobra result in serious local complications with extensive tissue necrosis and minimal neurotoxic symptoms. There is an apparent trend of favourable outcomes following the early administration of antivenom to patients without early signs of irreversible tissue damage. Further research is needed to evaluate the effectiveness of early antivenom use in Chinese cobra bites in order to minimise extent of tissue damage.

A Rare but Potentially Fatal Bacterial Infection in a Patient with Poorly Controlled Diabetes Mellitus: Emphysematous Pyelonephritis

Emphysematous pyelonephritis, a necrotizing infection of the renal parenchyma caused by gas-producing organism, is a rare but life-threatening condition. The initial presentation could be non-specific. We report a case of emphysematous pyelonephritis in a patient presenting with poorly controlled diabetes mellitus and severe sepsis. Its pathogenesis and management are briefly discussed.