Nutrition
Jan de Boer, Marcel Dubouloz in Handbook of Disaster Medicine, 2020
Severe vitamin A deficiency causes xerophthalmia, blindness and death. Clinical eye signs include: poor vision in dim light, dryness of conjunctiva or cornea, foamy material on the conjunctiva, or clouding of the cornea itself. These signs may appear after several months of an inadequate diet, or following acute or prolonged infections, particularly measles and diarrhoea. Mild/moderate vitamin A deficiency increases young-child mortality rates by about 20%. Clinical assessment reveals signs only in a very small proportion of subjects in populations affected by vitamin A deficiency and large numbers of children must be examined if this is the method of assessment used. Biochemical assessment is by the modified relative dose response (MRDR), which detects mild and moderate deficiency5.
Vitamin A
Judy A. Driskell, Ira Wolinsky in Sports Nutrition, 2005
Vitamin A, oxidized irreversibly to retinoic acid, is required for differentiation of epithelial tissues,17 including cornea and conjunctival membranes of the eye. Progressive deficiency of vitamin A causes xerophthalmia and eventually destruction of the cornea, resulting in total blindness. Other epithelial tissues (skin, respiratory pathways, urogenital tract) also become hyperkeratinized — thickened, dry and scaly — which prevents their normal function and facilitates infections. In addition, retinoic acid is involved in normal immune function, maintaining proper numbers of white blood cells (natural killer cells, various classes of lymphocytes).18 This role of retinoic acid is connected with the regulation of cell differentiation and proliferation, which leads to vitamin A involvement in normal reproduction, fetal development and growth. Retinoic acid regulates the expression of various genes encoding for important enzymes, structural proteins, transporters, receptors and growth factors. Specific patterns involving retinoic acid, retinoid receptors and retinoid-binding proteins were found to direct the embryonic development of vertebrae, spinal cord, limbs, viscera, eyes and ears, in timely and spatially appropriate sequence.19
Nutrition
Jagdish M. Gupta, John Beveridge in MCQs in Paediatrics, 2020
2.11. Which of the following statements is/are true?Xerophthalmia in a 3-year-old child is pathognomonic of vitamin A deficiency.Vitamin A overdose can cause raised intracranial pressure.Scurvy is rare in breast-fed infants.Vitamin D deficiency in infants can present with seizures.Vitamin E deficiency predisposes to haemolysis.
Clinical practice guidance for Sjögren’s syndrome in pediatric patients (2018) – summarized and updated
Published in Modern Rheumatology, 2021
Minako Tomiita, Ichiro Kobayashi, Yasuhiko Itoh, Yuzaburo Inoue, Naomi Iwata, Hiroaki Umebayashi, Nami Okamoto, Yukiko Nonaka, Ryoki Hara, Masaaki Mori
While 98% of adult SS patients complain of sicca symptoms, pediatric patients rarely complain of dryness [3,5,6]. Approximately 30% of cases present with sicca symptoms, which are detected by detailed medical interviews and examinations [24]. To assess dryness of the mouth (xerostomia), medical interviews should be conducted using specific close-ended questions as follows: ‘Do you need to drink water when eating dry foods like bread?’; ‘Are you worried about bad breath?’; ‘Have you ever experienced pain and/or enlargement of the parotid gland?’; ‘Do you have dental caries/stomatitis/ranula?’; ‘Have you noticed a change in your sense of taste?’. Parotid gland enlargement is frequently reported as the earliest symptom of SS [3–5,25]. Dry eye (xerophthalmia or keratoconjunctivitis sicca) symptoms, such as a feeling of dryness, red eyes, sensation of a foreign body, pain, and itchiness, should be checked, in addition to a condition where the patient cannot produce tears even when they might normally cry.
Interferon activation in primary Sjögren’s syndrome: recent insights and future perspective as novel treatment target
Published in Expert Review of Clinical Immunology, 2018
Iris L. A. Bodewes, Marjan A. Versnel
Primary Sjögren’s syndrome (pSS) is after rheumatoid arthritis (RA) the most common systemic autoimmune disease and affecting primarily post-menopausal women. pSS is characterized by focal lymphocytic infiltrations in salivary and lachrymal glands. Decreased secretory function of the glands leads to symptoms of dry eyes (keratoconjunctivitis sicca/xerophthalmia) and mouth (xerostomia). In approximately one-third of the patients, the symptoms of dryness are accompanied by systemic complications including multi-organ involvement and severe fatigue [1–3]. The etiopathology of the disease is still largely unknown and current treatment options are mainly targeting the symptomatic dryness. Interferon (IFN) activation is found in a large subset of pSS patients. These patients show upregulation of a set of IFN-stimulated genes (ISGs) also called the ‘IFN signature’. These upregulated genes influence multiple biological processes likely to play a role in the pathogenesis pSS. In this article, we summarize recent data on the role of IFNs in pSS pathogenesis and review the latest treatment strategies targeting IFNs.
Evaluation of Ocular Parameters in Adult Patients with Celiac Disease
Published in Current Eye Research, 2021
Leyla Hazar, Gülistan Oyur, Kadri Atay
The demographic characteristics of the study participants are shown in Table 1. The patients’ antibody values and iron and vitamin D levels are shown in Table 2. Intraocular pressure was similar in the two groups (p = .562). In the biomicroscopic evaluation, there was no finding related to xerophthalmia, such as Bitot’s spot corneal xerosis or ulceration/keratomalacia, in any of the patients. While there were no statistically significant group differences in terms of ACV and corneal thickness measured by the Sirius system, the ACD and ICA were found to be significantly higher in the celiac patients than in controls (Table 3). The RTVue OCT measurements revealed that the superior RNFL was significantly thinner and the nasal RNFL was thicker in celiac patients than in controls, while no difference was found in the average RNFL and inferior and temporal RNFL (Table 4). A Spearman’s correlation analysis revealed a significant negative correlation between the superior RNFL and presence of anti-tTG IgA antibody and a significant positive correlation between the ACV and AGA IgA in celiac group (Table 5).
Related Knowledge Centers
- Conjunctiva
- Cornea
- Corneal Ulcer
- Eye
- Nyctalopia
- Visual Impairment
- Vitamin A
- Vitamin A Deficiency
- Tears
- Dry Eye Syndrome