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Dermatological emergencies in pregnancy
Published in Biju Vasudevan, Rajesh Verma, Dermatological Emergencies, 2019
Riti Bhatia, Neirita Hazarika, Ruby Bhatia
Patients affected by trichothiodystrophy (TTD) have sulfur-deficient brittle hair and developmental abnormalities due to DNA repair and transcription gene defects. Pregnancies with affected fetuses are reported to have complications in the form of preeclampsia, decreased fetal movement, and HELLP (hemolysis, elevated liver enzymes, and low platelets) syndrome. In a study involving 27 TTD patients and their 23 mothers, 81% of the pregnancies had complications. These included preterm delivery (56%), preeclampsia (30%), placental abnormalities (19%), HELLP syndrome (11%), and fetal distress (4%). Other reported abnormalities include oligohydramnios, stillbirth, and placental asphyxiation. Prenatal diagnosis using fetal hair biopsy and DNA repair measurements is possible [38].
Photoexacerbated Dermatoses
Published in Henry W. Lim, Nicholas A. Soter, Clinical Photomedicine, 2018
Trichothiodystrophy is an autosomal recessive disease (X-linked in a single case) in which there is a reduced cystine/cysteine and sulfur content of the hair resulting in sparse, brittle, dry scalp, eyelash, and eyebrow hair (59). There is a variable association with neuroectodermal defects, leading to a question of whether trichothiodystrophy represents a subclass of the ectodermal dysplasias (59). Photosensitivity occurs as an exaggerated sunburn reaction in one-half of affected families (60). The action spectrum of the photosensitivity has not been determined, but fibroblasts and lymphocytes from photosensitive patients with trichothiodystrophy show decreased rates of unscheduled DNA synthesis in response to irradiation with UVC (60). Photosensitive trichothiodystrophy patients have been shown to share the XP group D mutation (60).
Genodermatoses affecting the nail
Published in Eckart Haneke, Histopathology of the NailOnychopathology, 2017
Xeroderma pigmentosum represents a group of autosomal recessive disorders of DNS repair rendering the affected individuals highly prone to develop skin cancers in sun-exposed skin. At least seven complementation groups (A–G) and a variant are differentiated.200 They differ in the chromosomal location of the gene defects, severity of ultraviolet sensitivity, frequency, and age of onset of malignancies. Xeroderma pigmentosum with mental deficiency, progressive neurologic deterioration, dwarfism, and gonadal hypoplasia was first described by A. Neisser in Breslau.201 Other syndromes were described, such as a combination with trichothiodystrophy features.202 From early infancy on, the skin develops diffuse erythema, scaling, and freckle-like hyperpigmentation. Within a few years, the skin becomes atrophic with mottled pigmentation and telangiectasiae resembling radiodermatitis and develops actinic keratoses. As early as in adolescence, skin cancers, mainly of the squamous cell type, but also basal cell carcinomas, melanomas,203 and rarely fibrosarcomas develop in sun-exposed skin, that is, also the dorsa of the hands, feet, and digits. Complete avoidance of sunlight prevents these changes (“moon-light children”).
Oliver McFarlane syndrome: two new cases and a review of the literature
Published in Ophthalmic Genetics, 2021
Kristian Lisbjerg, Mette K. G. Andersen, Mette Bertelsen, Agnes G. Brost, Frederik F. Buchvald, Rikke B. Jensen, Anne-Marie Bisgaard, Thomas Rosenberg, Zeynep Tümer, Line Kessel
Parents noticed visual difficulties from the age of two. At the age of three years, the patient underwent an ophthalmological examination at which point poor visual acuity equivalent to 20/200 (binocular) and a pale fundus with peripheral pigmentations was noted. The signs of severe chorioretinal degeneration were confirmed with ff-ERG that showed extinguished dark-adapted single flash and only a slight residual flicker response indicating absent rod function and very limited cone function. Complete night blindness was reported. The diagnosis at this point was early-onset retinitis pigmentosa. Fundoscopic findings were described as choroideremia-like. Due to dysmorphic features (Figure 1), growth retardation, and retinal degeneration a syndrome was suspected, and in the following years several clinical investigations were performed in the pursuit of a more exact diagnose. Chromosome analysis showed a normal female karyotype, 46,XX. The hair was examined for suspected Menkes disease or trichothiodystrophy but with no conclusive findings. At the age of three, thyroidal parameters were normal and clonidine stimulation of growth hormone (GH) also showed a normal result. Growth retardation persisted and by the age of 10, treatment with GH was initiated and she ended up with an adult height of 158 cm.
Amino acids profiles of children who stutter compared to their fluent sibling
Published in International Journal of Psychiatry in Clinical Practice, 2020
Mazin Alqhazo, Ayat Bani Rashaid
Limited studies focussed on the correlation between amino acid concentrations of human hair and diseases. Recently, a study conducted in Jordan comparing the concentrations of 14 amino acids in scalp hair of diabetic patients with age-sex matched healthy control. The outcome specified that glycine, glutamic acid, and isoleucine were significantly greater in the hair of patients diabetes type 2 compared with the hair of healthy subjects (Rashaid et al. 2015). The contents of amino acids have also been examined in the hair of Trichothiodystrophy (TTD) patients, a diminished content of cysteine was found in their hair samples (Sass et al. 2004). Moreover, significant decreases of arginine and methionine contents, as well as cysteine were displayed in hairs of patients with kwashiorkor (Takanohashi 1961; Metwalli et al. 1977).
Some mutations in the xeroderma pigmentosum D gene may lead to moderate but significant radiosensitivity associated with a delayed radiation-induced ATM nuclear localization
Published in International Journal of Radiation Biology, 2020
Mélanie Ferlazzo, Elise Berthel, Adeline Granzotto, Clément Devic, Laurène Sonzogni, Jean-Thomas Bachelet, Sandrine Pereira, Michel Bourguignon, Alain Sarasin, Mauro Mezzina, Nicolas Foray
Xeroderma Pigmentosum (XP) is a rare, autosomal, recessive genetic disorder usually characterized by high UV sensitivity, skin pigmentation, ocular surface diseases, high risk of skin cancers, and neurological degeneration. Cells from XP individuals show defective nucleotide excision repair (NER) of UV-induced DNA damage (Fassihi et al. 2016). Among the seven XP genes identified (XPA to XPG), the XPD gene (also called Excision Resynthesis Cross-Complementing gene 2 (ERCC2)) encodes for a 760 amino acid helicase protein involved in the human transcriptional factor IIH (TFIIH) complex and required for the NER pathway (Schaeffer et al. 1994). Mutations of the XPD gene can also result in two other genetic diseases, depending upon their domain localization: trichothiodystrophy (TTD), associated with sulfur-deficient brittle hair, unusual faces, mental retardation but not with skin cancer, and Cockayne’s syndrome (CS), associated with dwarfism, microcephaly, growth impairments, sun sensitivity, severe neurological abnormalities but not with skin cancer either (Lehmann 2001; Dubaele et al. 2003; Kraemer et al. 2007). XPD mutations were shown to result in impaired helicase activity and some of them may also prevent interaction with the p44 subunit of TFIIH (Dubaele et al. 2003). Interestingly, unlike for TTD, some cell lines from XPD and CS patients known for their sensitivity to UV may also elicit moderate but significant sensitivity to ionizing radiation (IR). However, CS patients have never been reported to develop cancer. Hence, among the three genetic syndromes caused by mutations in the XPD gene, only the XPD syndrome is associated with cancer proneness, which raises questions about the specific risk of post-radiotherapy tissue reactions in XPD patients (Arlett and Harcourt 1980; Deschavanne and Fertil 1996).