Pathogenesis and Clinical Approaches to Anticonvulsant Hypersensitivity Syndrome: Current State of Knowledge

Anticonvulsant hypersensitivity syndrome (AHS) is a rare, but severe and potentially fatal, adverse reaction that occurs in patients who are treated with commonly used older anticonvulsant drugs (phenytoin, carbamazepine and phenobarbital) and/or with some newer agents (lamotrigine). Paediatric patients are at an increased risk for the development of AHS for the higher incidence of seizure disorder in the first decade of life. Hypersensitivity reactions range from simple maculopapular skin eruptions to a severe life-threatening disorder. AHS is typically associated with the development of skin rash, fever and internal organ dysfunctions. Recent evidence suggests that AHS is the result of a chemotoxic and immunologically-mediated injury, characterized by skin and mucosal bioactivation of antiepileptic drugs and by major histocompatibility complex-dependent clonal expansion of T cells. Early recognition of AHS and withdrawal of anticonvulsant therapy are essential for a successful outcome. In vivo and vitro tests can be helpful for the diagnosis that actually depends essentially on clinical recognition.

Usefulness of Atopy Patch Test on a child with milk protein-induced enterocolitis syndrome: a case report

We describe the case of a child affected by milk-protein induced enterocolitis, in which oral challenge with corn was performed without symptoms after a negative specific Atopy Patch Test. Food protein-induced enterocolitis syndrome (FPIES) is an uncommon nonIgE-mediated gastrointestinal food hypersensitivity of infancy, characterized by severe vomiting and diarrhea arising within 1 to 3 hours after ingestion of the causative food. Little is known about the pathophysiology of FPIES. The absence of food-specific IgE as demonstrated by negative skin prick tests suggests that the disease is not caused by an early onset IgE-mediated reaction. Atopy Patch Test has been described as sensitive and predictive in this syndrome. The hypothesis on the immunological pathogenesis has been discussed on the basis of literature data.

Airway hyper-responsiveness to mannitol provides a good evaluation of atopy in childhood asthma

AIM

The relationship between airway hyper-responsiveness (AHR) and atopy has been previously investigated, but there are still some issues to be clarified. The aim of this study was to assess the link between AHR and mannitol and atopy in asthmatic children.

METHODS

We evaluated 44 children with asthma, aged 6-16 years of age, using skin prick tests (SPTs), serum total and specific immunoglobulin E (IgE) levels and the mannitol challenge test (MCT).

RESULTS

We found a good correlation between AHR to mannitol and specific IgE against Dermatophagoides pteronissinus (r = -0.66, p < 0.001) and a weak correlation with specific IgE against dog dander (r = -0.33, p = 0.01) and Aspergillus fumigatus (r = -0.23, p = 0.02). Furthermore, we found a weak correlation between AHR to mannitol and serum total IgE (r = -0.30; p = 0.03), the sum of specific IgE to aeroallergens (r = -0.37, p = 0.01) and the number of positive SPTs (r = -0.31, p = 0.02).

CONCLUSION

Measuring AHR with MCT might provide an accurate evaluation of the degree of atopy in children. The patients with a higher degree of atopy were significantly more reactive to mannitol. In clinical practice, these results indicate that children with asthma who are more atopic may require more intensive treatment strategies to reduce AHR.

Predisposing factors, clinical and microbiological aspects of bacterial keratitis: a clinical study

PURPOSE

To identify predisposing factors and to evaluate clinical and microbiological characteristics of bacterial keratitis.

MATERIALS AND METHODS

A retrospective analysis was performed on the charts of patients hospitalized for microbial keratitis and treated at the Department of Ophthalmology of the Policlinico Umberto I Hospital, Rome, Italy. The study was performed during a 42-month period. Risk factors, clinical and microbiological data were collected.

RESULTS

A total of 65 patients with bacterial keratitis were documented. Contact lens wear was the most common risk factor (46.1%). Trauma or a history of keratopathy was found in 18.5% and 15.4% of cases, respectively. An organism was identified in 62% of cases. 74% of all positive cultures involved gram negative bacteria. The most frequently cultured organism was Pseudomonas aeruginosa alone (72.2%) or in combination with other microorganisms (16.7%). Fifty-eight per cent of patients had visual acuity better than the level at admission, and 12% had very poor visual outcome.

CONCLUSIONS

Contact lens wear is the most important risk factor. The role of initial therapy for microbial keratitis remains important.

[Children's eye care in Italy through data provided by "Let's see clear" campaign]

PURPOSE

To know children's visual conditions and assess the actual status of ophthalmological prevention in Italy, highlighting both positive and negative aspects and its variables.

MATERIALS AND METHODS

Research was carried out in nine Italian regions (Sicilia, Calabria, Campania, Lazio, Abruzzo, Molise, Emilia Romagna, Lombardia, Friuli Venezia Giulia) by means of questionnaire filled in by preschool, elementary and junior high school children's parents. A different amount of questionnaires has been got for each region. For this reason a percentage distribution is used instead of absolute value, in order to remove distortion due to the different size of samples from region to region. Statistical analysis was carried out.

RESULTS

36.744 files were collected. Most important data were about (average):Parents' schooling (37% junior high school, 46% high school, 12% degree). 2. Spread of refractive errors (23% of children wear glasses). 3. Relation between children glasses (77% accepted glasses); 4. First ophthalmological examination: age (90% <6 yrs old in Lombardia), aim (77% prevention), who take the initiative (77% parents). 5. Relation between neonatal ophthalmological examination and premature birth or stay in incubator (Friuli: examination carried out on 63% of premature babies and on 79% of babies who needed the stay in the incubator). 6. The most common ocular diseases among children (subjective disorders 60%, motility disorders 20%, annexes' disorders 8%).

DISCUSSION

There are no many examples of studies about childhood health and even less frequent are the investigations about prevention and the diffusion of ophthalmological examination among children. Our data result from a pretty representative sample of Italian reality. The main feature of visual health among the children included in our research is the great spread of refractive errors, according to most economically advanced countries. Parents play a key role regarding childhood prevention, because they seem to have a high level of awareness in most included regions. Therefore, the family should represent the recipient of efforts in order to move up further the ophthalmological examination on children, preferably at birth.

Causes of blind certification in an Italian province and comparison with other European countries

PURPOSE

Low vision and blindness are significantly growing in both industrialized and developing countries. In Italy there are few epidemiological studies that provide data on this phenomenon. In this paper we report the main causes of blindness and the characteristics of the subjects who obtained a disability certification due to blindness in an Italian province.

MATERIALS AND METHODS

Disability certificates issued by the Civil Blind Provincial Commission of the Viterbo province over a 2-year period (2002-2003) were analysed. The causes of blindness and the age of occurrence were investigated and divided into 12 groups.

RESULTS

The four most frequent causes of blindness were age related macular degeneration (19%), cataract (14%), glaucoma (15%) and diabetic retinopathy (15%). The main eye pathology which caused partial blindness was age related macular degeneration (22.3%). Glaucoma (19.6%) was the main cause of total blindness.

CONCLUSIONS

The estimates of blindness were based on certification for visual impairment with limited characteristics as our data was exclusively administrative. However, a general appraisal of the magnitude and causes of visual impairment was determined. This is important towards planning appropriate preventive and management measures.