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 Table of Contents  
ORIGINAL ARTICLE
Year : 2019  |  Volume : 3  |  Issue : 1  |  Page : 72-77

A cross-sectional study of cutaneous changes in patients with acquired thyroid disorders


1 Department of Dermatology, Venereology and Leprology, AIIMS, Jodhpur, Rajasthan, India
2 Department of Dermatology, Venereology and Leprology, IGMC, Shimla, Himachal Pradesh, India
3 Department of Pathology, AIIMS, Jodhpur, Rajasthan, India

Date of Web Publication14-Feb-2019

Correspondence Address:
Anupama Bains
Department of Dermatology, Venereology and Leprology, Room No. 307, Resident Hostel, AIIMS, Basni Phase-2, Jodhpur - 342 005, Rajasthan
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/CDR.CDR_2_18

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  Abstract 


Background: Thyroid disorders are quite common in India. Thyroid hormone affects the skin and its appendages, and the cutaneous manifestations are more notable during deficiency or excess state. Apart from this, thyroid diseases are accompanied by various autoimmune dermatoses. Aim: The present study was designed to assess the dermatological manifestations in patients with thyroid disease. Materials and Methods: This was a hospital-based, cross-sectional, descriptive study conducted in a tertiary care center in Northern India over a period of 1 year. A total of 126 newly diagnosed patients with acquired thyroid disorders were enrolled in the study. All the patients were assessed for cutaneous, hair, nail changes, and associated autoimmune dermatological diseases. Results: Out of 126 patients, 113 had hypothyroidism and 13 had hyperthyroidism. Females outnumbered males in both the study groups. Some patients had more than one dermatological manifestation. The most common dermatological manifestation in hypothyroid patients was generalized xerosis (67.25%), followed by diffuse hair loss (47.78%) and coarse hair (44.24%). In hyperthyroid patients, the most common manifestation was thin soft hair (61.53%), followed by warm skin (53.84%) and Jellinek's sign (38.46%). Chronic urticaria was the most common associated autoimmune dermatological disease in both the study groups. Conclusion: In some instances, the initial and the most prominent complaint of the patient is related to alterations in the skin, and therefore, the dermatologist is at times being the first physician consulted. Identifying the endocrinopathy is very important so that the patients might receive corrective rather than symptomatic treatment.

Keywords: Dermatological manifestations, hyperthyroidism, hypothyroidism


How to cite this article:
Bains A, Tegta G R, Vedant D. A cross-sectional study of cutaneous changes in patients with acquired thyroid disorders. Clin Dermatol Rev 2019;3:72-7

How to cite this URL:
Bains A, Tegta G R, Vedant D. A cross-sectional study of cutaneous changes in patients with acquired thyroid disorders. Clin Dermatol Rev [serial online] 2019 [cited 2019 May 23];3:72-7. Available from: http://www.cdriadvlkn.org/text.asp?2019/3/1/72/252304




  Introduction Top


The skin is the largest and the most visible organ of the body and acts as a mirror to many systemic diseases. Endocrine diseases may cause manifestations in the skin and its adnexa. The most common among them worldwide are thyroid disorders. Cutaneous changes accompanying thyroid disease are neither unique nor pathogonomic. However, such cutaneous findings often provide important clues for the diagnosis of unsuspected thyroid disease. About 42 million people in India suffer from thyroid diseases.[1] The Northern Frontier of India including Himachal Pradesh forms the Himalayan goiter belt, and environmental deficiency of iodine is the primary factor responsible for endemic goiter in this region.[2]

Hypothyroidism results in pale, cool, and dry skin. The hallmark of hypothyroidism is myxedema. Hypohidrosis, palmoplantar keratoderma, purpura, xanthomatosis, coarse and sparse hairs, and brittle, striated, and slow-growing nails are other common cutaneous changes that occur in hypothyroidism. In the contrary, hyperthyroidism leads to warm, smooth skin, hyperpigmentation, palmar erythema, and facial flushing. Other manifestations are alopecia, soft nails, koilonychia, Plummer's nail, and thyroid acropachy.[3] Thyroid disorders may be associated with other autoimmune diseases such as alopecia areata, dermatitis herpetiformis, vitiligo, urticaria, and angioedema.[4] In this study, we aimed to assess the dermatological manifestations in patients with thyroid disease in this population since there has been no such previous study in this demographic profile.


  Materials and Methods Top


It was a hospital-based, cross-sectional, descriptive study conducted in a tertiary care center in Northern India over a period of 1 year, from August 2012 to July 2013. A total of 126 newly diagnosed patients with acquired thyroid disorders irrespective of the age and gender were included after taking informed consent. Thyroid function tests were done by enzyme-linked immunosorbent assay, and the following values were considered as normal.

  • Free T3 = 1.4–4.2 ρg/ml
  • Free T4 = 0.8–2.0 ηg/dl
  • TSH = 0.3–6.0 μIU/ml.


Exclusion criteria were pregnant and lactating women and patients with systemic diseases such as diabetes mellitus, renal, and liver disease. All the patients were assessed for cutaneous, hair, nail changes, and associated autoimmune dermatological diseases.


  Results Top


Out of 126 patients, 113 had hypothyroidism and 13 had hyperthyroidism. There was more than one medical symptom, cutaneous, hair, nail change, and associated autoimmune dermatological diseases in many patients.

Hypothyroidism

The age of hypothyroid patients ranged from 18 to 72 years with mean age of 44.04 ± 11.5 years. A maximum number of patients was in the age group of 41–50 years [Figure 1]. There was female predominance with male-to-female ratio of 1:36.6. The most common medical symptom noted in hypothyroid patients was lethargy seen in 70 (61.94%) patients, followed by weight gain in 51 (45.13%) patients and cold intolerance in 31 (27.43%) patients. Other findings were constipation in 28 (24.77%), dyspnea in 17 (15.04%), depression in 17 (15.04%), sleepiness in 15 (13.27%), decreased appetite in 15 (13.27%), menstrual abnormalities in 12 (10.90%), infertility in 10 (9.09%), hoarse voice in 10 (8.84%), and difficulty in concentration in 10 (8.84%) patients [Figure 2].
Figure 1: Age distribution of hypothyroid patients

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Figure 2: Medical symptoms in hypothyroid patients

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Cutaneous manifestations were seen in 85.84% of hypothyroid patients. The most common cutaneous finding was xerosis seen in 76 (67.25%) patients, followed by pale skin in 37 (32.74%) and acanthosis nigricans in 26 (23%) patients. Other findings were puffiness of hands and feet in 21 (18.58%), puffiness of face in 21 (18.58%), pruritus in 19 (16.81%), puffy eyelids in 17 (15.04%), acrochordon in 17 (15.04%), purpura/ecchymoses in 16 (14.15%), decreased sweating in 10 (8.84%), fine wrinkling in 8 (7.07%), asteatotic eczema in 7 (6.19%), and xanthelasma palpebrarum in 2 (1.76%) patients. [Table 1] shows the incidence of various cutaneous manifestations observed in hypothyroid patients. There were no cases of carotenemia, palmoplantar keratoderma, puffy lips, macroglossia, and myxedema. Hair changes were present in 62.83% of patients. The predominant finding was diffuse hair loss in 54 (47.78%) patients, followed by coarse and dry hair in 50 (44.24%) patients. Other findings were brittle hair in 21 (18.58%), slow growth in 17 (15.04%), loss of axillary hair in 16 (14.15%), loss of pubic hair in 8 (7.07%), and madarosis in 3 (2.65%) patients [Figure 3]. Nail changes were present in 36.28% of hypothyroid patients. The most common nail change was longitudinal striations seen in 39 (34.51%) patients, followed by brittle nails in 12 (10.61%) and slow growth in 2 (1.76%) patients. [Figure 4] shows various cutaneous manifestations of hypothyroidism such as xerosis, puffy eyelids with pale skin, purpura, xanthelasma palpebrarum, acanthosis nigricans, loss of axillary hair, madarosis, diffuse hair loss, and longitudinal striations.
Table 1: Cutaneous manifestations in hypothyroid patients (n=113)

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Figure 3: Hair changes in hypothyroid patients

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Figure 4: Dermatological manifestations in hypothyroid patients (a) xerosis, (b) puffy eyelids with pale skin, (c) purpura, (d) xanthelasma palpebrarum, (e) acanthosis nigricans, (f) loss of axillary hair, (g) madarosis, (h) diffuse hair loss, (i) longitudinal striations

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Associated cutaneous diseases were present in 52.21% of hypothyroid patients. Among these, chronic urticaria was the most common associated disease present in 18 (15.92%) patients followed by melasma in 11 (9.73%) patients. Other diseases were hirsutism in 8 (7.07%), alopecia areata in 6 (5.30%), angioedema in 4 (3.53%), symptomatic dermographism in 3 (2.65%), cutaneous amyloidosis in 3 (2.65%), polymorphic light eruption in 3 (2.65%), vitiligo in 3 (2.65%), psoriasis in 3 (2.65%), localized discoid lupus erythematosus in 1 (0.88%), lichen planus in 1 (0.88%), and dermatitis herpetiformis in 1 (0.88%) patient [Figure 5].
Figure 5: Associated cutaneous diseases in hypothyroid patients

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Hyperthyroidism

The age of hyperthyroid patients ranged from 18 to 55 years with mean age of 36.61 ± 12.5 years. Females outnumbered males with male-to-female ratio of 1:5.5. Among medical symptoms, fatigue was the most common symptom observed in 9 (69.23%) patients followed by weight loss in 7 (53.84%) patients. Other symptoms were heat intolerance in 7 (53.84%), hyperactivity in 5 (38.46%), palpitations in 5 (38.46%), goiter in 4 (30.76%), sweating in 3 (23.07%), diarrhea in 3 (23.07%), tremor in 3 (23.07%), proximal muscle weakness in 2 (15.38%), and lid lag in 1 (6.79%) patient [Figure 6].
Figure 6: Medical symptoms in hyperthyroid patients

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Cutaneous involvement was present in 69.23% of hyperthyroid patients. [Table 2] shows the incidence of various cutaneous findings found in hyperthyroid patients. The most common finding was warm skin present in 7 (53.84%) patients, followed by Jellinek's sign in 5 (38.46%) and pruritus in 4 (30.76%) patients. Other findings were smooth skin in 2 (15.38%), hyperhidrosis in 2 (15.38%), exophthalmos in 2 (15.38%), lid lag in 1 (7.69%), and hyperpigmentation in 1 (7.69%) patient. There were no cases of facial flushing, palmar erythema, and myxedema. Hair changes were seen in 69.23% of hyperthyroid patients. The most common findings were thin soft hair in 8 (61.53%) and diffuse hair loss in 4 (30.76%) patients. Soft and shiny nails were present in 30.76% of hyperthyroid patients. [Figure 7] shows various dermatological findings of hyperthyroidism such as Jellinek's sign, diffuse hair loss, and thin nail plate. Associated cutaneous diseases were present in 46.15% of hyperthyroid patients. These were chronic urticaria in 2 (15.38%), cutaneous amyloidosis in 1 (7.69%), symptomatic dermographism in 1 (7.69%), sweet syndrome in 1 (7.69%), and lichen planus in 1 (7.69%) patient.
Table 2: Cutaneous manifestations in hyperthyroid patients (n=13)

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Figure 7: Dermatological manifestations in hyperthyroid patients, (a) Jellinek's sign, (b) diffuse hair loss, (c) thin nail plate

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  Discussion Top


Disorders of thyroid may manifest in the form of hypothyroidism or hyperthyroidism with their various cutaneous manifestations.

Hypothyroidism

Mean age of patients was 44.04 years, while in other studies,[5],[6],[7],[10] the mean age ranged from 33.9 to 39.19 years which can be attributed to population bias. There was a female predominance like in other studies,[5],[6],[9],[10] with female-to-male ratio of 36.6:1. The most common medical symptom in hypothyroid patients was tiredness followed by weight gain which was consistent with the study of Keen et al.[10]

Cutaneous manifestations were seen in 85.84% of hypothyroid patients. [Table 1] represents the comparison of cutaneous findings between different studies. Generalized xerosis was the most common cutaneous manifestation seen in 67.25% of hypothyroid patients. A similar observation was made in other studies.[6],[9],[10] Xerosis sometimes may resemble acquired ichthyosis. Hypohidrosis accompanied by cytologic changes within the eccrine apparatus and diminished sebaceous gland secretion have been considered as potential etiologic factors.[14] In vitro studies have suggested that plasminogen activator, an enzyme implicated in the corneocyte shedding process, is decreased in T3 depleted keratinocytes.[15] Studies on thyroidectomized rats found that sterol synthesis is altered in epidermal keratinocytes deprived of thyroid hormone.[16] Hypothyroidism may hinder the epidermal barrier function by affecting the development of lamellar granules.[17] All these factors may have some role in the development of xerosis. Decreased sweating was present in 8.84% of patients which is in concordance with other studies.[10] We found pale skin in 32.74% of patients which was quite similar to the study done by Dogra et al.[6] Skin appears pale because of increased mucopolysaccharides and water content in dermis. Increase in dermal carotene because of altered Vitamin A metabolism may appear as a prominent yellow hue on the palms, soles, and nasolabial folds.[18] Puffy eyelids were seen in 15.04% of patients and puffy face, hands, and feet in 18.58% of patients. Periorbital edema mainly occurs due to the accumulation of glycosaminoglycans in the interstitial space.[7] Other studies reported a higher frequency of these findings.[10] This may be related to difference in sample size or can be due to difference in severity of the disease. We noticed generalized pruritus in 16.81% of patients which was quite similar to other studies.[10] Purpura was seen in 14.15% of patients. It occurs as a result of diminished levels of clotting factors or because of loss of vascular support secondary to dermal mucin.[19] Xanthelasma palpebrarum was found in 1.76% of patients. Similar findings were noted by other studies.[9],[10] Acanthosis nigricans and acrochordon were present in 23% and 15.04% of patients, respectively, while their incidence was low in the study by Keen et al.[10] Acanthosis nigricans and acrochordon possibly occur due to insulin resistance secondary to weight gain in hypothyroidism.[20] Diffuse hair loss was the second most common dermatological manifestation in hypothyroid patients. It was noticed in 47.78% of patients and was comparable to other studies.[6],[9],[10] T4 stimulates the proliferation of hair matrix keratinocytes, whereas their apoptosis is decreased by both T3 and T4. T4 prolongs the duration of anagen in vitro, by downregulation of TGF-2, the key anagen-inhibitory growth factor. Hypothyroidism has been proposed to cause premature catagen induction.[21] Coarse dry hair was present in 44.24% of patients while their frequency was less in other studies.[6],[10] Some patients had loss of axillary and pubic hair which was not seen in previous studies.[5],[6],[7],[9],[10] Madarosis was seen in 2.65% of patients. Other studies also found madarosis as the least common finding in hair changes.[6],[10] The most common finding in nails in patients of hypothyroidism was longitudinal striations (34.51%), followed by brittle nails (10.61%) and slow growth (1.76%). The results showed a varied pattern as compared to previous studies[5],[6],[7],[10] and may be related to the fact that these manifestations are not very unique to thyroid disorders and can be present in people not suffering from thyroid disease.

Association between thyroid diseases and various autoimmune diseases has been well documented in literature. In hypothyroid patients, chronic urticaria was present in 15.92%, angioedema in 3.53%, and symptomatic dermographism in 2.65% of patients. Leznoff was the first to demonstrate the link of chronic urticaria and angioedema with thyroid autoimmunity.[22] Various studies reported chronic urticaria in 13.04%–16.7% of patients.[6],[7],[9],[10] We observed alopecia areata in 5.30% patients. This association is established in various studies, such as those conducted by Thomas and Kadyan.[23] Vitiligo was present in 3(2.65%) hypothyroid patients. Various studies reported associated cases of vitiligo in 1.52% to 13.33% of patients.[5],[6],[7],[8],[9],[10],[24] Melasma was present in 9.73% of patients. Although the cause of melasma is not known, various studies reported incidence ranging from 14.28% to 18.75%.[5],[6],[9] Cutaneous amyloidosis was seen in 2.65% of patients. Dogra et al. reported it in 3.12% of patients.[6]

Hyperthyroidism

Mean age of hyperthyroid patients was 36.61 years with maximum number of patients in the age group of 31–50 years which was different from previous studies[11],[13] and may be attributed to population bias. Females outnumbered male like in other studies.[11],[12],[13] The most common medical symptom in hyperthyroid patients was fatigue followed by heat intolerance and weight loss. However, Rai et al. found loss of weight as the most common symptom.[13]

Cutaneous involvement was present in 69.23% of hyperthyroid patients. [Table 2] represents the comparison of cutaneous findings between different studies. The most common cutaneous manifestation in hyperthyroid patients was warm skin present in 53.84% of patients. A similar finding was reported in other studies.[11] There was low incidence of hyperhidrosis and exophthalmos as compared to previous studies.[13] This difference may be related to severity and duration of the disease. Warmth is caused by increased cutaneous blood flow and the sweating is a reflection of underlying metabolic rate.[18] Synergistic action between catecholamines and the thyroid hormones results in increased sweating.[25] Generalized pruritus was seen in 30.76% of patients which was quite comparable with previous studies.[13] Generalized hyperpigmentation was seen in 7.69% of patients and was quite similar to other studies.[11] Jellinek's sign was present in 38.46% of patients. There is speculation that the hyperpigmentation is due to increased release of pituitary adrenocorticotropic hormone compensating for accelerated cortisol degradation.[26] Smooth skin was seen in 15.38% of patients whereas other studies[11],[13] found a higher incidence. We observed thin, soft hair in 61.53%, diffuse hair loss in 30.76%, and soft and shiny nails in 30.76% patients. The results differed from previous studies[11],[13] and maybe because of small sample size in hyperthyroidism group. Among the various autoimmune diseases, chronic urticaria was present in 15.38% of hyperthyroid patients which was comparable with other studies.[13] Other associated diseases were cutaneous amyloidosis, symptomatic dermographism, sweet syndrome, and lichen planus which were seen in one patient each.


  Conclusion Top


Skin acts as an important diagnostic window to diseases affecting internal organs including thyroid disorders. Since many autoimmune skin diseases are associated with thyroid disorders, each patient presenting with these diseases should be screened for thyroid disorder in routine. Identifying the endocrinopathy is very important so that patients might receive corrective rather than symptomatic treatment.

Limitations of study

In this study, antithyroid antibodies were not estimated because of nonavailability of test in our hospital and cost factor. Further studies on a large cohort are required to augment the findings of our study.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the patients have given their consent for their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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Cox NH, Coulson IH. Systemic disease and the skin. In: Burns T, Breathnach S, Cox N, Griffiths C, editors. Rook's Textbook of Dermatology. UK: Wiley-Blackwell; 2010. p. 62.7.  Back to cited text no. 3
    
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Rai D, Wahid Z, Zaidi AN. Cutaneous manifestations of thyroid disease. J Pak Assoc Dermatol 2000;10:8-11.  Back to cited text no. 13
    
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Rosenberg RM, Isseroff RR, Ziboh VA, Huntley AC. Abnormal lipogenesis in thyroid hormone-deficient epidermis. J Invest Dermatol 1986;86:244-8.  Back to cited text no. 16
    
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    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7]
 
 
    Tables

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