Zika virus congenital syndrome: experimental models and clinical aspects

Viral infections have long been the cause of severe diseases to humans, increasing morbidity and mortality rates worldwide, either in rich or poor countries. Yellow fever virus, H1N1 virus, HIV, dengue virus, hepatitis B and C are well known threats to human health, being responsible for many million deaths annually, associated to a huge economic and social cost. In this context, a recently introduced flavivirus in South America, called Zika virus (ZIKV), led the WHO to declare in February 1st 2016 a warning on Public Health Emergency of International Concern (PHEIC). ZIKV is an arbovirus of the Flaviviridae family firstly isolated from sentinels Rhesus sp. monkeys at the Ziika forest in Uganda, Africa, in 1947. Lately, the virus has well adapted to the worldwide spread Aedes aegypti mosquito, the vector for DENV, CHIKV, YFV and many others. At first, it was not considered a threat to human health, but everything changed when a skyrocketing number of babies born with microcephaly and adults with Guillain-Barré syndrome were reported, mainly in northeastern Brazil. It is now well established that the virus is responsible for the so called congenital Zika syndrome (CZS), whose most dramatic features are microcephaly, arthrogryposis and ocular damage. Thus, in this review, we provide a brief discussion of these main clinical aspects of the CZS, correlating them with the experimental animal models described so far.(AU)

Zika virus congenital syndrome: experimental models and clinical aspects

Abstract Viral infections have long been the cause of severe diseases to humans, increasing morbidity and mortality rates worldwide, either in rich or poor countries. Yellow fever virus, H1N1 virus, HIV, dengue virus, hepatitis B and C are well known threats to human health, being responsible for many million deaths annually, associated to a huge economic and social cost. In this context, a recently introduced flavivirus in South America, called Zika virus (ZIKV), led the WHO to declare in February 1st 2016 a warning on Public Health Emergency of International Concern (PHEIC). ZIKV is an arbovirus of the Flaviviridae family firstly isolated from sentinels Rhesus sp. monkeys at the Ziika forest in Uganda, Africa, in 1947. Lately, the virus has well adapted to the worldwide spread Aedes aegypti mosquito, the vector for DENV, CHIKV, YFV and many others. At first, it was not considered a threat to human health, but everything changed when a skyrocketing number of babies born with microcephaly and adults with Guillain-Barré syndrome were reported, mainly in northeastern Brazil. It is now well established that the virus is responsible for the so called congenital Zika syndrome (CZS), whose most dramatic features are microcephaly, arthrogryposis and ocular damage. Thus, in this review, we provide a brief discussion of these main clinical aspects of the CZS, correlating them with the experimental animal models described so far.

Ocular abnormalities in multi‑transfused beta‑thalassemia patients.

Aims: The aim of this study was to assess ocular changes in thalassemia patients who have received multiple transfusions and chelate binding therapy in order to avoid iron accumulation. Settings and Design: A cross‑sectional study. Subjects and Methods: A total of 54 thalassemia major patients were selected as case group, and 54 age‑ and sex‑matched healthy subjects were regarded as a control group. Ocular examination included visual acuity, refraction testing, slit lamp examination, funduscopy, tonometry, perimetry, tear break‑up time test, and color vision testing were performed for all the participants. We computed the frequency and duration of blood transfusion, the mean serum ferritin level, pretransfusion hemoglobin concentration, and type, duration, and daily dose of chelation therapy for thalassemia patients based on their records. Statistical Analysis Used: All data analysis was performed using SPSS, version 19. Results: All the thalassemic patients were asymptomatic, but abnormal ocular findings (dry eye (33.3%), cataract (10.2%), retinal pigment epithelium degeneration (16.7%), color vision deficiency (3.7%), and visual field defects (33.7%)) were seen in 68.5% of thalassemic group. The prevalence of ocular abnormalities in normal group was 19.4%, which was significantly lower than that in thalassemia patients (P = 0.000). No significant correlation was found between ocular abnormalities and mean serum ferritin level (P = 0.627) and mean hemoglobin concentration (P = 0.143). Correlation of number of blood transfusion with the presence of ocular abnormalities was found to be statistically significant (P = 0.005). Conclusions: As life expectancy for beta‑thalassemia patients extends, regular ophthalmological evaluation to detect early changes in their ocular system is recommended.

Histologic Characteristics in the Eyes of DBA/2J Mice according to the Degree of Intraocular Pressure

PURPOSE: We assessed the correlation between ocular abnormalities and the degree of intraocular pressure (IOP) in the DBA/2J (D2) transgenic mice which were proven to have pigmentary dispersion syndrome and developing glaucoma. METHODS: Nine-months-old D2 mice were examined with biomicroscopy under anesthesia and measured for IOP by Tono-Pen, Hematoxylin and eosin staining was performed on the eye sections of the mice to analyze differences between the low-grade IOP group and the high-grade IOP group. RESULTS: Ocular abnormalities including iris pigment loss, iris transillumination, iris stromal atrophy, anterior synechia, thinning of the retina, and ganglion cell loss were found; all of which appeared to be pressure- dependent. CONCLUSIONS: These results corroborate that both IOP and age might be considered for studies using D2 mice, and suggest that D2 mice are a useful glaucoma model to study the mechanisms of retinal ganglion cell death and to evaluate strategies for neuroprotection.

The Ocular Disorders Observed in Patients with Vitiligo / 대한피부과학회지

BACKGROUND: Vitiligo is a common disorder caused by a loss of epidermal pigment cells. The pigment cells in the skin and uveal tract are similar in their physiology and morphology and share a common embryologic origin. OBJECT: The purpose of our study was to determine the nature of the relationship between vitiligo and ocular disease. METHODS: Fifty-two patients with vitiligo were examined for ocular abnormalities. RESULTS: There were 17ocular abnormalities our study; 5 fundal focal hypopigmented spots (9.6%), 6 iris pigment clumps(11.5%), and 6 lens opacity(11.5%). CONCLUSION: We believe that vitiligo may affect pigment cells in the eye. Therefore, all patients with vitiligo should have ocular examinations.

Strabismus and Refractive Errors in Cerebral Palsy Patients

OBJECTIVE: The purpose of this study was to compare the patients in the rehabilitation center with the patients who had visited the Department of Ophthalmology of Chonnam University Hospital to investigate incidence and type of ocular abnormalities in cerebral palsy patients. METHODS: We compared the seventy patients who had visited the Department of Ophthalmology of Chonnam University Hospital from January 1990 to July 2000 with one hundred and six patients in the rehabilitation center, and analyzed the incidence and type of ocular abnormalities between the two groups of cerebral palsy patients. RESULTS: In rehabilitation center group, spastic type was 51 patients among 90 patients (56.7%). In outpatient group, spastic type was 48 patients among 52 patients (92.3%). In rehabilitation center group, strabismus was detected in 35 patients among 106 patients (33.0%). In outpatient group, strabismus was detected in 31 patients among 70 patients (44.3%). In rehabilitation center group, refractive errors were detected in 27 patients among 85 patients (31.8%). In outpatient group, refractive errors were detected in 28 patients among 60 patients (46.7%). CONCLUSION: We concluded that because of the high incidence of ocular abnormalities in both rehabilitation center and outpatient groups, early detection through routine screening and early treatment for the ocular abnormalities of the cerebral palsy patients would be needed.