Post-acute phase and sequelae management of epidermal necrolysis: an international, multidisciplinary DELPHI-based consensus

BACKGROUND

Long-term sequelae are frequent and often disabling after epidermal necrolysis (Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN)). However, consensus on the modalities of management of these sequelae is lacking.

OBJECTIVES

We conducted an international multicentric DELPHI exercise to establish a multidisciplinary expert consensus to standardize recommendations regarding management of SJS/TEN sequelae.

METHODS

Participants were sent a survey via the online tool "Survey Monkey" consisting of 54 statements organized into 8 topics: general recommendations, professionals involved, skin, oral mucosa and teeth, eyes, genital area, mental health, and allergy workup. Participants evaluated the level of appropriateness of each statement on a scale of 1 (extremely inappropriate) to 9 (extremely appropriate). Results were analyzed according to the RAND/UCLA Appropriateness Method.

RESULTS

Fifty-two healthcare professionals participated. After the first round, a consensus was obtained for 100% of 54 initially proposed statements (disagreement index < 1). Among them, 50 statements were agreed upon as 'appropriate'; four statements were considered 'uncertain', and ultimately finally discarded.

CONCLUSIONS

Our DELPHI-based expert consensus should help guide physicians in conducting a prolonged multidisciplinary follow-up of sequelae in SJS-TEN.

Cicatricial Pemphigoid and Dry Eye

Cicatricial pemphigoid is the most common of the immunobullous disorders causing conjunctival cicatrization and is an autoimmune disease in which the ocular component of the immunopathology is directed at the conjunctival basement membrane. The disease is usually bilateral and more common in females, with most cases occurring between 30-90 years, and most often in the seventh decade. The disease occasionally occurs in children. Tear deficiency is a major cause of symptoms, although loss of vision is usually due to surface failure before the onset of aqueous tear deficiency, which occurs late in the progression of the disease. Management of the dry eye must be integrated with the management of the other components of both the ocular surface disease and inflammation. Management requires plastic surgery for the lid and lash malposition, tetracyclines and lid hygiene for the accompanying blepharitis. For the dry eye, the use of lubricants without preservatives is important, to avoid toxicity, and lubricant ointment is helpful for the relief of symptoms in terminally dry eyes without the capacity for surface wetting. Contact lenses, either large limbal diameter rigid gas permeable or gas permeable scleral lenses, are useful for treating dry eye and improving vision in some patients. Control of the conjunctival inflammation is mandatory to prevent disease progression and usually requires systemic immunosuppressive therapy.

Evaluation for farming systems improvement: looking backwards, thinking forwards

Based on personal reflection, this paper presents program evaluation as a vehicle to bring about better project results and perhaps even a better world. New paradigm approaches to farming systems improvement feature multiple collaborators in work that is increasingly participatory, process-oriented and diverse in outcome. This is often accompanied by pressure for rapid feedback and dialogue. Conventional objectives-based evaluation methods are insufficient to capture the range of unanticipated outcomes that this work may produce, and may be incompatible with a participatory ethos. In the contemporary farming systems improvement context, evaluation is most valuable when it has short-cycles and fosters reflection. Two contrasting techniques that offer promise for meeting these needs are the most significant change technique, and participatory approaches to program logic. Presenting a radical departure from conventional monitoring against quantitative indicators, most significant change technique involves the regular collection and participatory interpretation of ‘stories’ about change rather than predetermined quantitative indicators. Program logic is the rationale behind a program or project — what are understood to be the cause and effect relationships between project activities, outputs, intermediate outcomes, and ultimate outcomes. When done in group situations, program logic offers many benefits by enabling participants to question the cause and effect assumptions to improve project design. These techniques can supplement traditional approaches; closing some of the information gaps identified by contemporary farming systems improvement work.

Acanthamoeba Keratitis: The Role of Domestic Tap Water Contamination in the United Kingdom

PURPOSE

The incidence of acanthamoeba keratitis (AK) in the UK is some 15 times that in the United States and seven times that in Holland. To investigate reasons for this higher frequency, a study of the role of domestic tap water as a potential source of AK was undertaken.

METHODS

Tap outlets from the homes of 27 patients with culture-proven AK were sampled and cultured for free-living amoebae (FLA). For all Acanthamoeba isolates, mitochondrial DNA (mtDNA) restriction fragment length polymorphisms (RFLPs) and cytochrome oxidase (cox 1/2) sequence typing was performed to determine the similarity between corneal and tap water isolates.

RESULTS

FLA, including Acanthamoeba, were isolated from 24 (89%) of 27 homes, and the presence within the homes varied significantly with tap water temperature and location: 19 (76%) of 25 bathroom sink cold taps sampled compared with 6 (24%) of 25 hot and 9 (47%) of 19 kitchen cold taps compared with 3 (16%) of 19 of hot kitchen taps. Acanthamoeba were isolated from 8 (30%) of 27 homes (five bathroom sink cold taps, one cloakroom cold tap, one bath, and one bedroom sink mixer [hot/cold] taps). In six cases, identical Acanthamoeba mtDNA profiles were found for the clinical and home tap water isolates. In keeping with UK plumbing practice, 24 of 27 homes had internal roof water storage tanks to supply domestic taps, but the mains fed the kitchen cold tap.

CONCLUSIONS

Water storage tanks promote colonization of domestic water with FLA, including Acanthamoeba, and hence increase the risk of AK. This accounts for the significantly greater incidence of AK in the UK and supports advice to avoid using tap water in contact lens care routines.

Corneal toxicity: the epithelium and stroma in iatrogenic and factitious disease

Corneal toxicity is caused by chemical trauma and by iatrogenic and factitious disease, which are often overlooked, and which are reviewed here. The clinical signs of iatrogenic disease are usually nonspecific and identical to those resulting from other causes of surface disease. Factitious disease is either the result of mechanical trauma or the abuse of toxic eye drops. One epidemiological study, in a tertiary setting, identified 13% of keratoconjunctivitis cases as iatrogenic. Healing was prolonged taking 7-93 (median 28.5) days. Pathogenic mechanisms vary widely with different drugs and include subclinical scarring, pseudopemphigoid, drug-induced ocular cicatricial pemphigoid, and toxic follicular reactions. There is little readily available data either on the probability of the development of adverse reactions or for the comparison of different drugs. The assessment of the toxicity of topical drugs is currently by the Draize test in rabbits. New in vitro tests on human corneal epithelial cell cultures include ATP assays for cell viability, scanning EM of epithelial microvilli, and vital staining to assess cell membrane permeability and intracellular esterase. Despite their simplicity, these test systems can correlate well with clinical toxicity and provide a toxicity index for drug comparisons. Treatment requires drug withdrawal or substitution by non-preserved and less toxic preparations. Factitious injury is rare, difficult to diagnose, and should only be considered when all other diagnoses have been excluded. Prevention requires a high level of awareness of the potential for iatrogenic disease, particularly in the high-risk setting of chronic ocular surface disease.

Activity of the amidoamine myristamidopropyl dimethylamine against keratitis pathogens

OBJECTIVES

Microbial keratitis accounts for up to 30% of blindness in some less developed societies. The development of a single broad-spectrum topical antimicrobial effective against bacteria, fungi and Acanthamoeba would have a major impact on reducing the morbidity and simplifying the treatment of microbial keratitis. To this end, the activity of the amidoamine myristamidopropyl dimethylamine (MAPD) was investigated against common causes of microbial keratitis.

METHODS

Challenge test assays were used to study the efficacy of 50 mg/L MAPD against Pseudomonas aeruginosa, Staphylococcus aureus, Candida albicans, Fusarium solani and Acanthamoeba polyphaga.

RESULTS

MAPD gave a 3.7 log kill of P. aeruginosa after 60 min, 5.4 log for S. aureus by 45 min and 5 log for C. albicans and F. solani within 15 min. A. polyphaga cysts were reduced by 4 log within 120 min.

CONCLUSIONS

The findings of this study confirm that MAPD is an effective Acanthamoeba cysticidal agent and extend the observation to demonstrate that it also possesses excellent antifungal and antibacterial activity. MAPD may represent a broad-spectrum therapeutic antimicrobial for keratitis and surgical prophylaxis and deserves further evaluation in these roles.

Activities of therapeutic agents and myristamidopropyl dimethylamine against Acanthamoeba isolates

The activities of therapeutic agents and myristamidopropyl dimethylamine (MAPD) against Acanthamoeba strains recalcitrant to medical therapy were studied. MAPD minimum cysticidal concentrations were 6.25 to 25 microg/ml; 10 to 30 microg/ml gave at least a 3-log cyst kill after 6 h, and 50 and 100 microg/ml gave at least a 3-log cyst kill within 2 and 1 h, respectively.

Assessment of regional long-axis function during dobutamine echocardiography

Echocardiographic analysis of regional left ventricular function is based upon the assessment of radial motion. Long-axis motion is an important contributor to overall function, but has been difficult to evaluate clinically until the recent development of tissue Doppler techniques. We sought to compare the standard visual assessment of radial motion with quantitative tissue Doppler measurement of peak systolic velocity, timing and strain rate (SRI) in 104 patients with known or suspected coronary artery disease undergoing dobutamine stress echocardiography (DbE). A standard DbE protocol was used with colour tissue Doppler images acquired in digital ciné-loop format. Peak systolic velocity (PSV), time to peak velocity (TPV) and SRI were assessed off-line by an independent operator. Wall motion was assessed by an experienced reader. Mean PSV, TPV and SRI values were compared with wall motion and the presence of coronary artery disease by angiography. A further analysis included assessing the extent of jeopardized myocardium by comparing average values of PSV, TPV and SRI against the previously validated angiographic score. Segments identified as having normal and abnormal radial wall motion showed significant differences in mean PSV (7.9 +/- 3.8 and 5.9 +/- 3.3 cm/s respectively; P < 0.001), TPV (84 +/- 40 and 95 +/- 48 ms respectively; P = 0.005) and SRI (-1.45 +/- 0.5 and -1.1 +/- 0.9 s(-1) respectively; P < 0.001). The presence of a stenosed subtending coronary artery was also associated with significant differences from normally perfused segments for mean PSV (8.1+/-3.4 compared with 5.7+/-3.7 cm/s; P < 0.001), TPV (78 +/- 50 compared with 92 +/- 45 ms; P < 0.001) and SRI (-1.35 +/- 0.5 compared with -1.20 +/- 0.4 s(-1); P = 0.05). PSV, TPV and SRI also varied significantly according to the extent of jeopardized myocardium within a vascular territory. These results suggest that peak systolic velocity, timing of contraction and SRI reflect the underlying physiological characteristics of the regional myocardium during DbE, and may potentially allow objective analysis of wall motion.

Split thickness buccal mucous membrane grafts and beta irradiation in the treatment of recurrent pterygium

BACKGROUND

Pterygium is a common problem and after surgical removal may recur in up to 80% of cases, depending on the technique of primary excision. Recurrent pterygia can be aggressive and repeated excision may result in severe conjunctival scarring and shortening, resulting in insufficient conjunctiva to perform further grafting and lid surgery. When there is insufficient autologous conjunctiva, mucous membrane must be obtained from other sites. Full thickness buccal mucous membrane grafts have been described, but they may result in a beefy red appearance, with graft contraction and a poor tear film.

METHOD

The use of split thickness buccal mucous membrane grafts is described in three patients with recurrent pterygium, two in combination with lamellar keratoplasty. beta Irradiation was used as adjuvant therapy in all cases.

RESULTS

In all three cases an acceptable cosmetic appearance was achieved, with no recurrence of the pterygium, and a good range of eye movements.

CONCLUSIONS

It is recommended that split thickness buccal mucosal grafts, combined with beta irradiation, should be considered in complex cases of pterygium recurrence when there is insufficient autologous conjunctiva and conjunctival shortening with restricted eye movements.

Natural history of recurrent erosion syndrome--a 4 year review of 117 patients

AIMS/BACKGROUND

Recurrent erosion syndrome encompasses a group of mixed aetiologies for which there are a number of methods of management which may influence the course of the disease.

METHODS

The outcomes of a cohort of patients initially treated with topical lubricants were studied. 117 consecutive patients presenting over 1 year with a history of recurrent erosions were enrolled, baseline characteristics were documented, and treatment with lubricants was initiated. Patients were surveyed 4 years later inquiring about symptoms and treatments required.

RESULTS

A total of 94 (80%) of the initial cohort were contacted. The mean age was 44 years and the sex distribution was 44 males to 50 females. The mean period of follow up was 48 months. 55 (59%) were still symptomatic with attacks occurring at a median frequency of 60 days. 13 patients (24%) complained of an episode at least every week and 28 patients (51%) suffered at least every month. The median pain score (analogue scale of 1-10) was 2.5. Seventy five per cent (n = 21) of patients with epithelial basement membrane dystrophy (EBMD) were symptomatic compared with those with a traumatic aetiology among whom 46% (n = 28) were symptomatic. This difference was significant (p = 0.02). Those with EBMD were more likely to be continuing to use topical lubricants than the trauma group.

CONCLUSION

Patients with a traumatic aetiology are less likely to suffer chronic recurrent erosion syndrome than those with EBMD.

The inside story: why contact lens cases become contaminated

Contact lens case contamination has become an enigma, both because its role in the pathogenesis of lens-related keratitis has remained uncertain, and because current contact lens disinfection systems have been ineffective in eliminating it. This lecture reviews the evidence regarding the role of lens case contamination in the pathogenesis of keratitis and examines the reasons for the failure of disinfection systems to minimise lens case contamination.

Biomechanical analysis of two change-of-direction maneuvers while running

Many research efforts focus on unidirectional gait. However, few functional activities are exclusively linear: people regularly change directions to evade obstructions. Directional changes have been identified as particularly hazardous, but rarely studied. The purpose of this study was to examine the kinetics of abrupt changes of direction while running. Twelve adult volunteers performed 10 trials each for 45 degrees and 90 degrees change-of-direction conditions. Orthogonal force and moment (torque) records were obtained using a computer-interfaced force platform system. Vertical, braking, and propulsive force and applied torque variables were extracted for statistical analysis. Significant force differences (p < .01) were identified between conditions. Applied torques were highly variable and not significantly different. Functionally, these data suggest that applied forces serve as the principal impetus of directional change.

Pseudomonas keratitis associated with biofilm formation on a disposable soft contact lens

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Nonulcerative complications of contact lens wear. Relative risks for different lens types

A case-control study was used to evaluate the relative risk (RR) of acute contact lens-related disorders. The study sample comprised new patients wearing contact lens presenting at the accident and emergency department at Moorfields Eye Hospital, London, England, in 12 months. Disorders were classified by pathogenesis. Compared with gas-permeable hard contact lenses (the referent), extended-wear soft contact lenses were related to the largest overall RR for any complication (2.7 [95% confidence limits, 1.73, 4.16]), whereas for daily wear soft contact lenses the overall RR was 1.3 (confidence limits, 1.0, 1.72). Relative risks were greatest for extended-wear soft contact lens wearers with metabolic disorders (2.1 [confidence limits, 1.28, 3.4]) and for such wearers with sterile infiltrates (2.4 [confidence limits, 1.22, 4.84]). Among those using daily wear contact lenses, RR was highest for those with toxic/hypersensitivity disorders (5.9 [95% confidence limits, 3.27, 10.49]). Severe complications involving greater morbidity occurred more frequently with extended-wear soft contact lenses. This could be reduced by selecting a more appropriate lens type to correct low refractive errors.

Possible environmental sources of Acanthamoeba spp in contact lens wearers

The water supply and dust samples from the home environment (bathrooms and kitchens) of 50 wearers of contact lenses (CLs) were cultured for the presence of free-living amoebae. CL cases, solutions, and water taps were cultured for bacteria, which amoebae require for growth. Acanthamoeba spp were isolated from water drawn from six bathroom cold water taps (tank supplied), five in the presence of limescale, and from one kitchen cold water tap (mains supplied). There was an association between the presence of limescale in water and direct culture for free-living amoebae, suggesting that scale provides a favourable microenvironment for amoebae. Acanthamoebae were also found in dust from around one washbasin. Nineteen of 50 CL cases, 12/122 CL care rinsing solutions, and 59/100 cold water taps yielded Gram negative bacteria which could be ingested by amoebae. It is concluded from this study that CLs should not be washed in first-drawn tank-fed cold water, especially if limescale is present, and that soft CLs should be rinsed in manufactured single-use, sterile solutions. Rigid CL and CL cases should only be washed with boiled tap water (preferably hot), or single-use sterile solutions, and stored dry to prevent multiplication of amoebae and Gram negative bacteria.