Presence and prevalence of UV related genetic mutations in uveal melanoma: similarities with cutaneous melanoma

Ultraviolet (UV) radiation is an accepted etiological factor in cutaneous melanoma (CM), however its role in uveal melanoma (UM) is controversial. Partly as a consequence, CM and UM are often considered to be separate conditions, and advances in the treatment of CM have not led to joint clinical trials or parallel improvements in survival of UM. This study hypothesized that a subset of UM tumors displays evidence of genetic changes consistent with UV-related damage similar to that shown in CM. Analysis of the Broad Institute's Firebrowse depository of 80 UM samples and 343 CM samples, together with the Sanger Institute's Catalogue of Somatic Mutations in Cancer depository of 995 UM and 12,447 CM samples was undertaken to identify the most frequently mutated genes, mutation types, and specific nucleotide variants (SNVs) in each condition. Somatic mutation data were cross-correlated and shared mutations assessed against known effects of UV radiation. The proportion of samples with C>T substitutions (a classic genetic marker of UV-related damage) was higher in UM than CM on both DNA strands (17.0% vs 13.1%, p=0.038). The most frequently encountered cross-correlated mutated genes between UM and CM were, in order, BRAF, NRAS, TP53, CDKN2A, TERT, PTEN, ARID2, and KMT2C, with multiple common BRAF point mutations. Each cross-correlated mutation, and each common point mutation in BRAF, was associated with UV-related mechanistic changes. These findings support the hypothesis that the etiology of a substantial minority of UMs may be more UV dependent than previously recognized.

Evolving systemic targeted therapy strategies in uveal melanoma and implications for ophthalmic management: a review

Uveal melanoma (UM) is the most common primary ocular tumour in adults. Despite good local control of the primary tumour with current methods, survival after the development of metastasis has remained poor over the last 30 years. After cutaneous melanoma, UM is the most common type of melanoma, and an ongoing debate exists regarding whether these conditions should be considered separate entities, particularly in the context of targeted therapy, where many of the initial trials for patients with metatatic cutaneous melanoma excluded metastatic UM. This paper will review the recent and ongoing investigations designed to validate systemic targeted therapy and immunotherapy in patients with metastatic UM and suggests ways in which these developments may affect management of UM by ophthalmologists in the near future.

Different surgical treatments for nasal septal perforation and their outcomes

OBJECTIVE

To critically evaluate the literature on surgical treatment options for nasal septal perforations and to analyse the outcomes of these treatment options.

DESIGN

A systematic review of studies of nasal septal perforation closure using surgical intervention, published from January 1975 to March 2006.

DATA SOURCES

Forty-nine papers were identified from electronic databases (all Evidence Based Medicine reviews (Cochrane Database of Systematic Reviews, American College of Physicians Journal Club, Database of Abstracts of Reviews of Effectiveness and Cochrane Controlled Trials Register), EMBASE, Ovid (Medline) and British Medical Journal publications) and from a hand search of the reference lists of retrieved papers. Textbooks pertinent to the subject were referred to for background reading. Twenty-three studies met the inclusion criteria.

MAIN OUTCOME MEASURE

Effectiveness of the surgical intervention to completely close the perforation.

RESULTS

Five studies examined the sole use of intranasal mucosal flaps to close the perforation, i.e. inferior turbinate flaps, quadrangular cartilage flap and mucoperiosteal flap. Eighteen studies reported the use of a combination of intranasal mucosal flap and interposition graft. Graft materials included temporalis fascia, mastoid periosteum, nasal septal material, acellular human dermal graft, conchal cartilage and porcine small intestine mucosa. Studies utilising interposition grafts generally produced higher closure rates. The surgical approaches documented include closed endonasal, unilateral hemitransfixion, external rhinoplasty and midfacial degloving techniques. A range of surgical treatment methods was reported in the literature, but some papers were excluded from this review as they did not meet the inclusion criteria. It was difficult to infer the true effectiveness of each study as the subject numbers were small, patient selection criteria were often unspecified and the follow-up period was brief. However, factors leading to an increased chance of success were identified.

CONCLUSION

The review found an extensive range of surgical treatment techniques, but reported results were rarely statistically significant. It is difficult to be categorical about the effectiveness of a surgical treatment method; nonetheless, each technique has its own advantages and drawbacks.

Open lung biopsy for diffuse parenchymal lung disease in children

An open lung biopsy was performed in 12 children with diffuse parenchymal lung disease. A definitive histopathological diagnosis was obtained from all procedures but determined treatment options in only 10 children (83%). Three (25%) children were ventilated for respiratory failure prior to the procedure. Four (44%) of the other 9 children required ventilatory support after the procedure. Three (25%) children developed post-op pneumothorax that resolved fully with chest tube drainage. There were no deaths as a direct result of the procedure. Open lung biopsy is useful in providing a definitive diagnosis in children with diffuse parenchymal lung disease and determining treatment in the majority of cases. The procedure was well-tolerated with minimal complications.

Paediatric utilization of a general emergency department in a developing country

AIM

Knowledge of the spectrum and frequencies of pediatric emergencies presenting to an emergency department (ED) of individual developing countries is vital in optimizing the quality of care delivered locally.

METHODS

A prospective 6 wk review of all pediatric (< 18 y) attendees to an urban ED was done, with patient age, presenting complaints, diagnoses, time of arrival and disposition recorded.

RESULTS

Complete data were available on 1172 patients, with an age range of 4 d to 18 y (mean +/- SD 6.9 +/- 5.6 y); 43% were aged < or = 4 y. The main presenting complaints were injuries (26.9%), fever (24%) and breathing difficulties (16.6%). The most common diagnosis was minor trauma (24.2%), with soft-tissue injuries predominating (80.6%). The other diagnoses were asthma (12.6%), upper respiratory infections (12.1%), other infections (12.1%) and gastroenteritis (11.8%). Equal proportions of patients were seen throughout the day. 25% of patients were admitted. Young age (< 1 y); presence of past medical history, general practitioner referrals, diagnosis of bronchiolitis and pneumonia were significantly associated with risk of admission.

CONCLUSION

A wide spectrum of paediatric illnesses was seen in the ED, with an overrepresentation of young children. This supports the decision to have either a separate pediatric ED or paediatric residents on the staff. The training curricula should emphasize the management of pediatric trauma, infections and asthma. Alternatively, developing guidelines for the five most common presenting complaints would account for 82% of all attendees and could be directed towards all staff on the ED.

Paediatric admissions at a tertiary hospital in Kuala Lumpur--a case for a short-stay ward

The profile of admissions staying less than 24 hours admitted to the paediatric wards of University Malaya Medical Center, Kuala Lumpur, over a period of six weeks was reviewed to ascertain the need of a short-stay ward. Ninety-three (22%) of the 428 admissions admitted during the study period were discharged within 24 hours, 56 (60%) were discharged within 12 hours. Major categories of admissions were: elective investigative procedures (43%), and emergency admissions (44%). Reasons for emergency admissions: infections 42%, minor trauma/cerebral concussion 25% and febrile/afebrile seizures 11%. Only 20% required percutaneous oximetry monitoring and 2% required observations more frequently than 2 hourly. There may be a case for a short stay ward in a big paediatric unit in Malaysia.

Low-dose inhaled nitric oxide in term and near-term infants with hypoxic respiratory failure: a Malaysian experience

Inhaled nitric oxide (iNO) improves oxygenation in term and near-term infants with persistent pulmonary hypertension of the newborn (PPHN) and decreases the need for treatment with extracorporeal membrane oxygenation (ECMO). This mode of treatment is currently being introduced in Malaysia. We report our preliminary experience using low dose inhaled nitric oxide (20 parts per million) in three newborn infants (meconium aspiration syndrome, primary PPHN and congenital diaphragmatic hernia) with severe PPHN who fulfilled criteria for ECMO with a mean oxygenation index (OI) of 40. Two of the infants showed rapid and sustained improvement in oxygenation with a reduction in oxygenation index (OI) over 24 hours. The infant with diaphragmatic hernia showed an initial improvement in OI, which was unsustained and subsequently died. All three infants did not show significant elevation of methemoglobin or nitrogen dioxide (NO2). Inhaled nitric oxide is an effective and safe treatment for severe PPHN that can be used in a developing country like Malaysia.

Centralization of paediatric intensive care: are critically ill children appropriately referred to a regional centre?

OBJECTIVES

To evaluate the appropriateness of emergency referrals for inter-hospital transfers by local physicians in hospitals without intensive care facilities to a regional tertiary paediatric intensive care unit (PICU).

DESIGN

A prospective, descriptive study in a tertiary PICU and hospitals without paediatric intensive care facilities in and around the London area, UK.

PATIENTS

All patients (< 18 years) referred for emergency admission to the PICU from district hospitals (n = 436) as well as those admitted through other modes of admission (n = 286) between 1 October 1998 and 30 June 1999 were prospectively studied. Admissions and transfers were deemed appropriate if the risk of mortality using the Paediatric Risk of Mortality (PRISM II) score was greater than 1%, and/or if the patient required a unique ICU-dependent therapy. Effectiveness was estimated using PRISM II derived observed-to-expected mortality ratio. Of the 436 emergency referrals 398 (91.3%) were retrieved and transported to the PICU. Of these, 38 referrals were thought to be inappropriate after telephone consultation and were not transferred. Of the emergency referrals 376 (94.4%) had a mortality risk greater than 1% or required an ICU-dependent therapy on admission day. Thus 86.2% (376/436) of the referrals and 94.4% (376/398) of transfers were considered appropriate. The PRISM II derived standardized mortality rate was 0.694 (95% CI 0.517-0.913) in the overall population and 0.613 (95% CI 0.434-0.843) amongst the emergency referrals.

CONCLUSION

Physicians at local hospitals within a centralized system of delivering paediatric intensive care were able to maintain adequate assessment skills in recognition and requesting for appropriate transfers of the most ill and efficiently utilized resources available at the regional centre.

Identifying futility in a paediatric critical care setting: a prospective observational study

AIMS

To determine the extent of futile care provided to critically ill children admitted to a paediatric intensive care setting.

METHODS

Prospective evaluation of consecutive admissions to a 20 bedded multidisciplinary paediatric intensive care unit of a North London teaching hospital over a nine month period. Three previously defined criteria for futility were used: (1) imminent demise futility (those with a mortality risk greater than 90% using the Paediatric Risk of Mortality (PRISM II) score); (2) lethal condition futility (those with conditions incompatible with long term survival); and (3) qualitative futility (those with unacceptable quality of life and high morbidity).

RESULTS

A total of 662 children accounting for 3409 patient bed days were studied. Thirty four patients fulfilled at least one of the criteria for futility, and used a total of 104 bed days (3%). Only 33 (0.9%) bed days were used by patients with mortality risk greater than 90%, 60 (1.8%) by patients with poor long term prognosis, and 16 (0.5%) by those with poor quality of life. Nineteen of 34 patients died; withdrawal of treatment was the mode of death in 15 (79%).

CONCLUSIONS

Cost containment initiatives focusing on futility in the paediatric intensive care unit setting are unlikely to be successful as only relatively small amounts of resources were used in providing futile care. Paediatricians are recognising futility early and may have taken ethically appropriate measures to limit care that is futile.

Impact of 24 hour critical care physician staffing on case-mix adjusted mortality in paediatric intensive care

The 24 h availability of intensive care consultants (intensivists) has been shown to improve outcomes in adult intensive care units (ICU) in the UK. We tested whether such availability would improve standardised mortality ratios when compared to out-of-hours cover by general paediatricians in the paediatric ICU setting of a medium-income developing country. The standardised mortality ratio (SMR) improved significantly from 1.57 (95%CI 1.25-1.95) with non-specialist care to 0.88 (95%CI 0.63-1.19) with intensivist care (rate ratio 0.56, 95% CI 0.47-0.67). Mortality odds ratio decreased by 0.234, 0.246 and 0.266 in the low, moderate and high-risk patients. 24 h availability of intensivists was associated with improved outcomes and use of resources in paediatric intensive care in a developing country.

Severe bronchiolitis in Malaysian children

Twenty-two (42 per cent) out of 52 patients admitted with severe bronchiolitis to our Paediatric Intensive Care Unit required ventilation. Risk factors associated with ventilation included a younger mean age, female sex, low birthweight, failure to thrive and the presence of an underlying illness. Ventilated patients were also more likely to have a higher respiratory distress assessment index (RDAI) score, pneumonic infiltration on chest X-ray, lower serum sodium and a positive respiratory syncytial virus isolation in the tracheal secretion.

Swyer-James-MacLeod syndrome

Swyer-James-MacLeod syndrome is a rare complication of respiratory tract infection occurring in early childhood. We report two children with chronic cough and recurrent wheezing who fulfilled the diagnostic criteria for this disorder: 1) Unilateral loss of lung volume with hyperlucency on chest x-ray. 2) Unilateral reduction in vascularity on CT scan of the chest. 3) Unilateral loss of perfusion on Technetium 99c lung scan.

Paediatric intensive care in Kuala Lumpur, Malaysia: a developing subspecialty

Paediatric intensive care in Malaysia is a developing subspecialty with an increasing number of specialists with a paediatric background being involved in the care of critically ill children. A part prospective and part retrospective review of 118 consecutive non-neonatal ventilated patients in University Hospital, Kuala Lumpur was carried out from 1 June 1995 to 31 December 1996 to study the clinical epidemiology and outcome in our paediatric intensive case unit (PICU). The mean age of the patients was 33.9 +/- 6.0 months (median 16 months). The main mode of admission was emergency (96.6 per cent) with an overall mortality rate of 42 per cent (50/118). The mean paediatric risk of mortality (PRISM) score was 20 +/- 0.98 SEM, with 53 per cent of patients having a score of over 30 per cent. Multiorgan dysfunction (MODS) was identified in 71 per cent of patients. Admission efficiency (mortality risk > 1 per cent) was 97 per cent. Standardized mortality rate using PRISM was an acceptable 1.06. The main diagnostic categories were respiratory (32 per cent), neurology (22 per cent), haematology-oncology (18 per cent); the aetiology of dysfunction was mainly infective. Non-survivors were older (29.5 vs. 13.8 months, p < 0.0001), had more severe illness (mean PRISM score 30 vs. 14, p < 0.0001), were more likely to develop MODS (96 vs. 53 per cent, p < 0.0001) and required more intervention and monitoring. Paediatric intensive care in Malaysia differs widely from that in developed countries in patient characteristics, severity of illness, and care modalities provided.

Respiratory failure requiring ventilation in acute bronchiolitis

Severe bronchiolitis requiring mechanical ventilation is uncommon and is associated with the risk of barotrauma. We report our experience with 25 (42%) of 60 infants admitted to the Paediatric Intensive Care Unit (PICU) with severe bronchiolitis who required mechanical ventilation. Eighteen patients (72%) had severe hypoxaemia (PaO2/FiO2 < 250). The mean airway pressure required ranged from 5.8 to 15.6 cmH2O with median ventilation duration of 4.0 days (range 2.0-14.0 days). Oxygenation improved significantly within 12 hours of intubation. There was only one death. Mechanical ventilation is required in a subset of patients for severe bronchiolitis and is effective and generally well tolerated.

Corticosteroid rescue in late paediatric acute respiratory distress syndrome

Late acute respiratory distress syndrome (ARDS) is associated with a mortality of more than 80%. Recent reports in adults have shown improved survival in late ARDS treated with prolonged course of steroids, however little data are available in children concerning its safety and efficacy. We report the successful treatment of a child dying from refractory late ARDS using a prolonged course of high-dose methylprednisolone instituted after 12 days of advanced mechanical ventilation. Progressive improvement was seen from days 3, 7, 10 and 14 after treatment with improvement in PaO2/fraction of inspired oxygen (FiO2) ratios, lung injury score and chest radiographical score. Treatment was complicated by a fungal urinary tract infection that was easily controlled. There were no major metabolic side effects. Steroid therapy can be considered in the treatment of children with refractory late ARDS but larger prospective studies are needed to define indications, timing, dosing and safety of this mode of treatment in children.

Viral aetiology of lower respiratory tract infection in young Malaysian children

OBJECTIVE

To study the viral aetiology of lower respiratory tract infection (LRTI) in young Malaysian children.

METHODOLOGY

A retrospective review was performed of LRTI patients aged less than 24 months who were admitted to the University Malaya Medical Centre between 1982 and 1997. Respiratory viruses in their nasopharyngeal secretion were identified by indirect immunofluorescence, viral culture, or both.

RESULTS

A total of 5691 children were included in the study. The mean age was 8.6 +/- 6.6 months and the M:F ratio was 1.6:1. The most common diagnosis was pneumonia (52%) followed by bronchiolitis (45%) and croup (2%). Positive viral isolation rate was 22.0%. Respiratory syncytial virus (RSV) was the commonest virus isolated (84%), followed by parainfluenza virus (8%), influenza virus (6%) and adenovirus (2%). Patients with positive virus isolation were younger (7.8 +/- 6.2 vs 8.7 +/- 6.7 months, P = 0.0001) and were more likely to have bronchiolitis.

CONCLUSION

Young Malaysian children admitted with LRTI had a 22% viral isolation rate and RSV was the commonest virus isolated.

Withdrawal and limitation of life support in paediatric intensive care

OBJECTIVES

To compare the modes of death and factors leading to withdrawal or limitation of life support in a paediatric intensive care unit (PICU) in a developing country.

METHODS

Retrospective analysis of all children (< 12 years) dying in the PICU from January 1995 to December 1995 and January 1997 to June 1998 (n = 148).

RESULTS

The main mode of death was by limitation of treatment in 68 of 148 patients, failure of active treatment including cardiopulmonary resuscitation in 61, brain death in 12, and withdrawal of life support with removal of endotracheal tube in seven. There was no significant variation in the proportion of limitation of treatment, failure of active treatment, and brain death between the two periods; however, there was an increase in withdrawal of life support from 0% in 1995 to 8% in 1997-98. Justification for limitation was based predominantly on expectation of imminent death (71 of 75). Ethnic variability was noted among the 14 of 21 patients who refused withdrawal. Discussions for care restrictions were initiated almost exclusively by paediatricians (70 of 75). Diagnostic uncertainty (36% v 4.6%) and presentation as an acute illness were associated with the use of active treatment.

CONCLUSIONS

Limitation of treatment is the most common mode of death in a developing country's PICU and active withdrawal is still not widely practised. Paediatricians in developing countries are becoming more proactive in managing death and dying but have to consider sociocultural and religious factors when making such decisions.

Pulmonary nocardiosis in a child with hyperimmunoglobulin E syndrome

Hyperimmunoglobulin E syndrome (HIE) is a rare condition characterised by marked elevation of serum IgE level, chronic dermatitis, intense pruritus, and recurrent serious infection. The major organism is usually S aureus. We report a case of an infant with HIE, who had pulmonary nocardiosis. The clinical features, immunological abnormalities, and radiological features of the condition are described. The child finally succumbed to the complications of pulmonary nocardiosis.

Acute myopathy after status asthmaticus: steroids, myorelaxants or carbon dioxide?

Acute myopathy complicating treatment of status asthmaticus has been increasingly recognized since its original description in 1977. We report a case of an 11-year-old boy with severe asthma requiring mechanical ventilation. He was given high doses of parenteral steroids and neuromuscular blockade with non-depolarizing agents in order to achieve controlled hypoventilation with an ensuing hypercapnoea. He developed rhabdomyolysis with elevated creatinine kinase and renal impairment secondary to myoglobinuria. Electrophysiological studies revealed myopathic abnormalities. The aetiology for this myopathy appears to be related to therapy with parenteral steroids, muscle-relaxant agents and respiratory acidosis. Patients treated with steroids and neuromuscular blocking agents should be regularly monitored for development of myopathy.

Surfactant replacement therapy in RSV-induced acute respiratory distress syndrome (ARDS)

Acute respiratory distress syndrome (ARDS) associated with severe respiratory syncytial virus infection is rare. We report a 5-month-old Indian girl who was admitted to our intensive care ward with severe respiratory failure who fulfilled the criteria for ARDS using both Murray's Lung Injury Score of > 2.5 and the American-European Consensus Conference definition for ARDS. She developed diffuse bilateral alveolar infiltrates, severe hypoxaemia (PaO2/FiO2 < 100) and required high PEEP (> 15 cm H2O) 24 hours after admission. RSV was isolated from her nasopharyngeal secretion. She also had clinical features suggestive of a primary immunodeficiency and had laboratory evidence of combined T and B cell defect. There was unsustained clinical improvement with a dose of surfactant administered at 36 hours of PICU stay, and she continued to deteriorate and succumbed after 19 days in the PICU.

Percutaneous central venous catheterisation in critically ill children

An 18-month analysis of 52 percutaneously placed central venous catheters in 48 critically ill children was done. Success rate were 91.7% (33/36) and 93.8% (15/16) for femoral and non-femoral catheters respectively. Presence of hypotension (48.1%) and significant coagulopathy (26.9%) did not affect the success rate significantly. Minor bleeding and venous congestion was seen in 5.5% (2/36) of patients with femoral catheters. Infections were found in 2.7% (1/36) of femoral and 6.6% (1/15) of non-femoral catheters. The low incidence of complications and the relative ease of insertion makes the femoral route the preferred site for trainee medical officers in critically ill children when central access is indicated.

Fatal enterovirus 71 encephalomyelitis

During an outbreak of hand-foot-mouth disease caused by enterovirus 71 (EV-71) in 1997, 4 children presented with sudden cardiopulmonary collapse and minimal neurologic features. All children received cardiopulmonary resuscitation but died within a few hours of admission. Postmortem studies showed infection by EV-71 with extensive damage to the medulla and pons. We postulate an etiologic link between EV-71 and brainstem encephalomyelitis as the cause of pulmonary edema and death.

Incidence of acute respiratory distress syndrome: a comparison of two definitions

OBJECTIVES

To determine the incidence and outcome of acute respiratory distress syndrome (ARDS) in children by comparing two commonly used definitions: the lung injury score and the American-European Consensus Conference definition. The causes and risk for developing ARDS were also studied.

METHODS

Part prospective and retrospective analysis of 8100 consecutive hospital admissions from 1 June 1995 to 1 April 1997.

RESULTS

Twenty one patients fulfilled the criteria for ARDS. Both definitions identified the same group of patients. The incidence was 2.8/1000 hospital admissions or 4.2% of paediatric intensive care unit admissions. The main causes were sepsis and pneumonia. Mortality was 13 of 21. Factors predicting death were a high admission paediatric risk of mortality (PRISM) score (30.38 v 18.75) and the presence of multiple organ dysfunction syndrome (92% v 25%).

CONCLUSION

Both definitions identified similar groups of patients. The incidence in this population was higher than that reported elsewhere, but mortality and cause were similar to those in developed countries. Poor outcome was associated with sepsis, a high admission PRISM score, and simultaneous occurrence of other organ dysfunction.

Intestinal lymphangiectasia--a report of three Chinese children in Malaysia

This is a report of 3 Chinese children with intestinal lymphangiectasia in Malaysia. Two children responded to a low fat diet and medium-chain triglyceride supplement. The third child has recurrent chylous ascites. None of the children has recurrent infections despite low CD4+ cells and low levels of IgG and IgA. Intestinal lymphangiectasia is a rare congenital disorder of the mesenteric lymphatic that leads to the obstruction of the lymphatics of the intestine and protein losing enteropathy. Restriction of dietary fat intake will usually result in remission. Recurrent chylous ascites is a problem and management can be difficult.