Tuesday, March 31

Nevus of Ota

  ›     ›   Nevus of Ota.
What is nevus of Ota?
Nevus of Ota is a hamartoma of dermal melanocytes. Ota lesion was first described by Dr. Masao.T. Ota, from the University of Tokyo, Japan in 1939 as "nevus fuscoceruleus opthalmomaxillaris".
Ota lesion is also known as "congenital melanosis bulbi" or "oculodermal melanocytosis". Ota lesion presents as a blue/grey patch on the facial skin, ocular area and/or oral/nasal mucosal surfaces. The lesions occur in the areas covered by the first and second (ophthalmic and maxillary) branches of the trigeminal nerve. The hyperpigmentation is usually unilateral and in several cases it involves the sclera.

Nevus of Ota is caused by entrapment of melanocytes in the dermal layer. Ito lesion, Hori's macule and Mongolian spot also occur due to the entrapment and hamartomatous growth of melanocytes. In Ito lesions, only shoulder and upper arm are involved. Mongolian spots appear on lumbosacral region. Hori's macule is not present at birth and often affects both sides of the face. Though Ota lesions are mostly congenital, there are reports of a few cases acquired during puberty, indicating the possible role of hormones.
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Amiya Kumar Mukhopadhyay described a very rare presentation of simultaneous presence of unilateral Ota lesion, bilateral Ito lesion and palatal lesions in a male patient.

The incidence of these lesions in women is nearly five times more than men. It is more prevalent in Asian, African and East Indian populations and very rare among caucasian people. After onset, nevus of Ota may keep pace with the child's growth and may slowly and progressively enlarge and darken in color. The lesion usually become stable in appearance once adulthood is reached. Patients had reported of fluctuations in color of these lesions with environmental and health factors. Tanino had classified Ota lesions into type I (mild), type II (moderate), type III (intensive) and type IV (bilateral).

Nevus of Ota pathogenesis

The exact etiology of Ota lesion is still unknown. These lesions are caused by the presence of melanocytes in the dermis and the bluish/greyish coloration of the lesion is due to Tyndall effect of the dermal melanocytes. The failure of the melanocytes/melanoblasts from the neural crest to migrate to the epidermis during the embryonic stage is postulated as a cause. Another view is that the lesions are formed due to active production by intradermal melanocytes or due reactivation of pre-existing latent dermal melanocytes. Though specific genetic cause is not identified, a familial case has been reported. Exogenous and endogenous factors such as warm or cold weather, emotional stress, fatigue and insomnia may alter the intensity of color. Hormonal fluctuations as in menstrual cycle and menopause may increase the intensity of pigmentation.

Nevus of Ota treatment

Small disfiguring lesions can be covered up by cosmetic camouflage. Topical therapy appears to be ineffective. Other treatment modalities such as dermabrasion, micro surgery and cryotherapy may produce scars.
Ota lesion in the sclera
Nevus of Ota
Laser treatment and intense pulsed light are used to destroy these melanocytes. Multiple treatments with a combination of devices may be required. There is always the likelihood of these lesions recurring.

Sanjeev Aurangabadkar reported his study to evaluate long-term safety and efficacy of QYAG5 Q-switched Nd:YAG Laser Treatment of Ota lesion. Fifty patients with Ota lesions underwent multiple treatments over a period of one year with a Q-switched Nd:YAG laser (QYAG5, Palomar, USA). He reported excellent improvement in a majority of the patients and there were no significant adverse effects. Transient post-inflammatory hyperpigmentation was observed in some patients with resolution in two months. There was no recurrence of Ota lesion in one year of follow up.

Nevus of Ota complications

In rare cases melanoma has been reported to arise from the Ota lesions. Most of cases of malignant melanoma developing from the lesions are mainly found in skin. Ocular melanoma has been reported in the choroid, orbit and iris, in association with a Ota lesion. Some patients may develop intracranial neoplasia. Cherungottil V Radhadevi et al. reported a rare case with malignant transformation in oculodermal melanosis.

Ota lesion may give rise to ocular complications such as increased intraocular pressure and glaucoma. Lidija Magarasevic et al. reported a case of an appearance of unilateral glaucoma in a Caucasian female patient with the acquired, ipsilateral nevus of Ota.
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Reference:
1.Lidija Magarasevic, Zihret Abazi. “Unilateral Open-Angle Glaucoma Associated with the Ipsilateral Nevus of Ota,” Case Reports in Ophthalmological Medicine, vol. 2013, Article ID 924937, 3 pages, 2013.
2.Ravi Prakash Sasankoti Mohan, Sankalp Verma, Amit Kumar Singh, Udita Singh. ‘Nevi of Ota: the unusual birthmarks’: a case review. BMJ Case Rep. 2013; 2013: bcr2013008648.
3.Jitender Solanki, Sarika Gupta, Nisha Sharma, Meenakshi Singh, Sumit Bhateja. Nevus of Ota”- A Rare Pigmentation Disorder with Intraoral Findings. J Clin Diagn Res. 2014 Aug; 8(8): ZD49–ZD50.
4.Cherungottil V Radhadevi, Kakkuzhiyil S Charles, Vasu K Lathika. Orbital malignant melanoma associated with nevus of Ota. Indian J Ophthalmol. 2013 Jun; 61(6): 306–309.
5.Gaurav Sharma, Archna Nagpal. Nevus of Ota with Rare Palatal Involvement: A Case Report with Emphasis on Differential Diagnosis. Case Rep Dent. 2011; 2011: 670679.
6.Amiya Kumar Mukhopadhyay. Unilateral Nevus of Ota with Bilateral Nevus of Ito and Palatal Lesion: A Case Report with a Proposed Clinical Modification of Tanino's Classification. Indian J Dermatol. 2013 Jul-Aug; 58(4): 286–289.
7.Sanjeev Aurangabadkar. QYAG5 Q-switched Nd:YAG Laser Treatment of Nevus of Ota: An Indian Study of 50 Patients. J Cutan Aesthet Surg. 2008 Jul-Dec; 1(2): 80–84.
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Image source: http://en.wikipedia.org/wiki/File:Nevus_013.jpg
Author: Luninsky | License: CC BY 3.0
Current topic in natural skin care: Nevus of Ota.

Wednesday, March 25

Giant congenital melanocytic nevus - Giant hairy nevus

  ›     ›   Giant hairy congenital melanocytic nevus.
What is congenital melanocytic nevus?
The congenital melanocytic nevus (CMN) is a dark, pigmented, often hairy patch of skin. A congenital melanocytic nevus is present at birth or appears soon after birth.
It is the benign proliferation of a variant of melanocytes known as nevus cells. They are anomaly in embryogenesis and are considered as malformations or hamartomas.

The congenital melanocytic nevus lesions, are classified according their sizes. There are several classification systems proposed, but the system proposed by Kopf et al. is the most accepted. The CMN lesion present at birth that will reach a diameter of 20 cm or more in adulthood is classified as giant congenital melanocytic nevus (aka bathing trunk nevus, garment nevus or giant hairy nevus). The CMN lesions having a diameter less than 2 cm are considered as small-sized and those having a diameter more than 2 cm but less than 20 cm are considered as medium-sized.

Giant congenital melanocytic nevus (GCMN)

The giant congenital melanocytic nevus is a rare entity and its incidence is about one in every 20,000 births.
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These lesions present as brown, dark brown and black patches with well-demarcated borders. The surface may be flat, mammillated, papular, roughed, warty or cerebriform. Often the lesions are hairy. Normally, giant CMN is asymptomatic, but some patients may complain of pruritus.

Some peculiar locations and shapes of the hairy nevi lead to use of descriptive terms like 'garment', 'bathing trunk', 'shirt', 'coat sleeve' or Hairy giant nevus. Satellite lesions, small pigmented lesions scattered over the body, are observed in nearly 80% of the giant CMN patients. Satellite lesions associated with giant hairy CMN may be present in odd places like oral cavity, scalp, eyelids and planter areas. The giant hairy CMN may disturb the skin structure, causing cutaneous fragility, impaired sebaceous and eccrine glands and superficial ulcers.

Psychosocial issues

The unsightly appearance of the hairy nevi is psychosocially devastating for the affected person and his family members. The psychological consequences of the hairy nuvi in visible areas like face are many. Nearly 25% of the patients suffer from emotional or behavioral problems. Nearly 30% of patients have to face social problems. The impaired self-image caused by the presence of the giant hairy CMN, the anxiety over the risk of complications and the unsightly appearance contribute in compounding the psychological symptoms in the patients and other family members.

Pathogenesis

The giant congenital melanocytic nevus lesion originates during 5th and 24th week of gestation.
Giant hairy congenital melanocytic nevus in a young girl with signs of neurocutaneous melanosis
Giant hairy congenital melanocytic nevus in a young girl with neurocutaneous melanosis
It is due to a morphological error occurring in the neuroectoderm during embryogenesis. The abnormal accelerated proliferation of the precursor cells of melanocytes (melanoblasts) leads to the pigmented and hairy nevus. The hepatocyte growth factor is a cytokine regulator of epithelial cells and overexpression of this factor can lead to discrepancies and disparities in differentiation, proliferation and migration of melanoblasts/melanocytes.

The size of the hairy nevus depend upon how early the accelerated proliferation of cells of melanocyte lineage has started. The melanocyte proliferation commencing after birth produces acquired melanocytic nevus. A small CMN will result if the proliferation of melanocytes in the dermal-epidermal junction begins shortly before birth. Giant and medium-sized nevi would develop when the proliferation starts, during migration of melanoblasts from the neural crest to epidermis. The giant congenital hairy nevus will be large and deep seated if the proliferation starts during the embryonic or early fetal periods.

Progression over time

The progression over time of the hairy lesions is unpredictable. Some GCMN may get lightened over time whereas some may darken. As the hairy lesion progresses the pigmentation may get more heterogeneous or homogeneous. The hairy growth may increase over time. In some patients the hairy growth may disappear. In very rare cases the giant congenital hairy lesions may spontaneously regress. In some cases it was reported that the lesions darkened through adolescence and then significantly lightened. The surface undergoes changes such as increase in roughness, thickness, hairy growth and appearance of nodules.

Health risks from giant congenital melanocytic nevus

The giant congenital melanocytic nevus in some cases develop into malignant melanoma or neurocutaneous melanosis with melanocytic tumors in the leptomeninges. The estimated lifetime risk of developing melanoma varies from 5 to 10%. There is the possibility for simultaneous occurrence of disorders like diffuse lipomatosis, atrophy and asymmetry of limbs, scoliosis, urinary tract anomalies, cafe-au-lait spots and Mongolian spots.

Melanoma associated with hairy giant congenital melanocytic nevus

The melanoma affecting patients with GCMN occurs usually in the dermis or in deeper layers. Most of other melanomas arise in the epidermis. In a study of 289 patients with hairy giant congenital melanocytic nevus, Dedavid et al. found 67 cases of melanoma. 50.7% of these melanoma appeared on the lesions. 3% of the melanomas appeared on clinically normal skin. 31.3% of them were primary central nervous system (CNS) tumors and 15% were metastatic tumors spread from unknown primary site.

Patients having multiple satellite nevi and hairy giant congenital melanocytic nevus on locations such as the back, neck or head have the increased risk of developing melanoma. The probability of a GCMN patient developing melanoma is more in the early childhood. Dedavid et al. found that 50% of the melanomas were diagnosed before five year age. Benign tumors may also develop on the hairy melanocytic nevus.

Neurocutaneous melanosis (NCM)

Neurocutaneous melanosis is a congenital disorder associated with the presence of giant congenital nevus on the skin and melanocytic tumors in the leptomeninges. These lesions occur in brain and spinal cord. Nearly 50% of the patients with NCM develop malignancy. It occurs in the form of leptomeningeal melanoma. The cause is believed to be related to abnormal development of melanoblasts and mutations of the NRAS gene. Some of the symptoms of NCM are, increase in intracranial pressure, seizures, vomiting, headache and papilledema. There is no effective treatment for the disorder.

Treatment

Several treatment options are available for treating hairy congenital melanocytic nevus. The age of the patient, size and location of the lesion and risk of melanoma are to be considered while selecting a treatment option. Surgery, dermabrasion, skin curettage, chemical peels and laser treatment are the options available.
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Reference:
1.Arpaia N, Cassano N, Filotico R, Laricchia F, Vena GA. Unusual clinical presentation of regression in a congenital melanocytic nevus. Dermatol Surg 2005;31:471-3.
2.Martín JM, Jordá E, Calduch L, Alonso V, Revert A. Progressive depigmentation of a palmar congenital melanocytic nevus without an associated halo phenomenon. Dermatology 2006;212:198-9.
3. Nath AK, Thappa DM, Rajesh NG. Spontaneous regression of a congenital melanocytic nevus. Indian J Dermatol Venereol Leprol 2011;77:507-10.
4.Gass JK, Grant JW, Hall PN, Atherton DJ, Burrows NP. Clinical resolution of a neonatally eroded giant congenital melanocytic nevus. Pediatr Dermatol 2006;23:567-70.
5.Ana Carolina Leite Viana, Bernardo Gontijo, Flávia Vasques Bittencourt. Giant congenital melanocytic nevus. An Bras Dermatol. 2013 Nov-Dec; 88(6): 863–878.
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Current topic in natural skin care: Giant congenital melanocytic nevus - Giant hairy nevus.

Wednesday, March 18

Zinc for hair growth - Zinc deficiency hair loss

  ›     ›   Zinc for hair growth - Zinc deficiency hair loss.
Zinc is an essential micronutrient, having important functions in biochemical processes in the body. Zinc is essential for protein synthesis, nucleic acid synthesis, cellular functions and several enzymatic processes.
zinc deficiency disorders, either acquired or congenital, manifest with common symptoms such as hair loss and dermatitis. Several research studies have proved that zinc deficiency affects the healthy growth and function of skin and its appendages such as hair, sebaceous glands, sweat glands, fingernails and toenails.

Zinc deficiency causes

The primary cause of deficiency is insufficient levels of the mineral in the diet. Another cause is inefficient uptake from the food, though the food may contain sufficient amounts of the mineral. Other causes are, genetic factors, malabsorption syndromes and increased gastrointestinal and urinary losses. Chronic liver disease, ulcerative colitis, chronic renal disease, Crohn’s disease, sickle cell disease, diabetes, short bowel syndrome, cancer, other chronic illnesses, gastrointestinal surgery and chronic diarrhea may also cause deficiency of the mineral.
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Certain medications, minerals and chemicals may interact and affect its absorption and utilization. Quinolone antibiotics and tetracycline antibiotics affect the absorption of zinc in the intestine and thiazide diuretics increase its urinary excretory loss. High doses of iron and copper can affect the absorption of this mineral from the intestine.

Acrodermatitis enteropathica (Brandt syndrome or Danbolt–Closs syndrome) is a congenital metabolic disorder affecting the uptake of zinc. It is characterized by skin inflammation around the natural orifices and extremities, loss of hair and diarrhea.

Research on zinc deficiency hair loss

In a study carried out by Min Seong Kil et al. at Hallym University Kangdong Sacred Heart Hospital (Seoul, Korea), 312 patients with main complaint of alopecia were enrolled for the study "Analysis of Serum Zinc and Copper Concentrations in Hair Loss". The blood samples were analyzed for serum zinc and copper concentrations. The results revealed that, in hair loss patients, the serum zinc concentration was significantly lower than that of the control group, but the serum copper concentration was not significantly different.

Min Seong Kil et al. observed that "zinc-related metalloenzymes may have the potential to regulate hair growth. Zinc is a component of zinc finger motifs for many transcription factors, which regulate hair growth through hedgehog signaling, and is a catagen inhibitor via its inhibitory action on apoptosis-related endonucleases." They concluded that the mineral metabolism disturbances play a key role in hair loss, especially alopecia areata and telogen effluvium loss.

How zinc deficiency affects hair

Among the important functions of the mineral in the human body, the regulating of follicle cycling, inhibiting follicle regression and accelerating follicle recovery are noteworthy. Paus et al.20 reported that zinc has a potent dose-dependent immunomodulatory effect on the follicles. It is also a potent inhibitor of follicle regression and accelerates follicle recovery.

Even transient zinc deficiency is known to have an effect on the follicle function. The cellular processes like protein synthesis, cell division, cell repair, enzymatic reaction, utilization of vitamins are directly affected by the deficiency of zinc. Its deficiency weakens the structural integrity of the follicles. The deficiency the micronutrient leads to disturbances in the follicle cycling and anagen phase and also premature advancement of resting telogen phase. With retardation of anagen phase, the fresh supply of new hair strands is affected leading to more follicles in resting phase. The end effect is thinning of strands and apparent excessive loss.

Zinc deficiency can cause subclinical hypothyroidism which is known to cause hair loss. Ambooken Betsy et al. in their study 'Zinc Deficiency Associated with Hypothyroidism: An Overlooked Cause of Severe Alopecia' reported that "Hypothyroidism is a common and well recognized cause of diffuse hair loss". They added that "The hair loss attributed to hypothyroidism may not improve with thyroxine unless zinc supplements are added."

Correcting zinc deficiency

Oysters, red meat, poultry, whole grains, dairy products, fortified cereals, beans, chickpeas and nuts are good sources. Supplements may be taken under the advice of the health care provider to correct the deficiency. Overdose of zinc can cause acute adverse effects and deficiency of other micronutrients. Patients with hereditary haemochromatosis may accumulate the mineral in their body. Very high doses of zinc are reported to inhibit both the anagen and catagen stages of hair growth.
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Reference:
1.Ambooken Betsy, MP Binitha, and S Sarita. Zinc Deficiency Associated with Hypothyroidism: An Overlooked Cause of Severe Alopecia. Int J Trichology. 2013 Jan-Mar; 5(1): 40–42.
2.The Office of Dietary Supplements, National Institutes of Health.
http://ods.od.nih.gov/factsheets/Zinc-HealthProfessional/
3.Min Seong Kil, Chul Woo Kim, Sang Seok Kim. Analysis of Serum Zinc and Copper Concentrations in Hair Loss. Ann Dermatol. 2013 Nov; 25(4): 405–409.
4.Karashima T, Tsuruta D, Hamada T, Ono F, Ishii N, Abe T, Ohyama B, Nakama T, Dainichi T, Hashimoto T. Oral zinc therapy for zinc deficiency-related telogen effluvium. Dermatol Ther. 2012 Mar-Apr;25(2):210-3.
5.Paus R, Christoph T, Müller-Röver S. Immunology of the hair follicle: a short journey into terra incognita. J Investig Dermatol Symp Proc. 1999 Dec;4(3):226-34
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Current topic in natural skin care: Zinc deficiency hair loss.

Wednesday, March 11

Iron for hair growth - Iron deficiency hair loss

  ›     ›   Iron for hair growth - Iron deficiency hair loss.
Iron (Fe) deficiency affects hair growth, and chronic lack of iron in the diet can lead to hair loss. Nutritional deficiencies of vitamins as well as that of minerals such as, zinc, copper and iron are associated with hair loss.
For finding a solution to this common problem, the main focus must be to investigate the nutritional shortcomings. The cardinal point to be borne in mind is that healthy balanced food leads to healthy body.

In the human body, the total iron is about 3.8 grams in men and 2.3 grams in women. It is present in all cells of the human body, including hair follicles and red blood cells. Unlike minerals such as calcium, sodium and magnesium, the iron in the blood plasma is not in a free ionic form and is bound tightly to the protein transferrin. Free iron is toxic to cells as it catalyzes in the formation of free radicals. Iron is a key component of cytochrome in cells, which are primarily responsible for the generation of ATP via electron transport and catalyze several redox reactions. Iron is also stored in the cells as ferritin.
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Iron is the key component of protein hemoglobin present in the red blood cells. It facilitates oxygen absorption in the lungs and oxygen transport to cells. Sufficient oxygen supply is necessary for keeping the follicles healthy and any deficiency in oxygen supply can induce telogen effluvium. Myoglobin is an iron containing protein found in the muscles. It has the property of binding to oxygen and functions in oxygen storage. Fe is also important for removing carbon dioxide generated in the tissues during oxidation of glucose and transporting it to lungs for exhalation.

Iron deficiency and hair loss

Iron deficiency is the most prevalent nutritional deficiency in the world. Iron deficiency anemia is very common among women of childbearing age. Iron deficiency in the body leads to decrease in hemoglobin, myoglobin and ferritin stores. It causes deprivation of sufficient oxygen to the body tissues and muscles and manifest as symptoms like tiredness, fatigue, dizziness, pallor, hair loss, irritability and inability to concentrate.

Causes of deficiency

Many conditions lead to deficiency of this mineral in the body. Both insufficient intake as well as depletion and loss from the body lead to anemia.
  • The foremost reason for the mineral deficiency is insufficient intake through food.
  • Protein-energy malnutrition, malnutrition, starvation, anorexia nervosa and other eating disorders can give rise to various health problems, including iron deficiency and hair loss.
  • Excessive menstrual bleeding in women is the major cause of iron depletion from the body.
  • Chronic bleeding wounds, bleeding from the gastrointestinal tract, bleeding piles, bleeding gastric ulcers and bleeding colonic cancer are some of the conditions causing the deficiency.
  • Malabsorption syndromes like inflammatory bowel disease, Crohn's disease, ulcerative colitis and celiac disease can hamper absorption of the mineral as well as cause its depletion by bleeding.
  • Surprisingly, athletes can become anemic due to mechanical hemolysis, destruction of red blood cells from physical impact, especially among long distance runners. They may also suffer loss of iron through sweat, urine and intestines.

Ferritin (iron store) and hair loss

Ferritin is an intracellular protein that stores iron and controls its release. It acts as a buffer in case of Fe deficiency or overload. Though most of the ferritin is stored in the cells, small amounts are released into the blood plasma as an Fe carrier. The serum ferritin level correlates with total body iron stores. However, in case of infection or chronic inflammation the serum ferritin levels get elevated and do not correlates with total body Fe stores.

Moeinvaziri M et al in their study, 'Iron status in diffuse telogen hair loss among women', concluded that, "In women without systemic inflammation or other underlying disorders, serum ferritin levels below or equal to 30 ng/mL are strongly associated with telogen loss."

The normal range of serum ferritin for men is between 12-300 ng/ml and for women is 12-150 ng/ml. However the optimum level is 70 ng/ml and above. It is to be noted that a person may have normal hemoglobin levels and may not show any anemia symptoms. However, he may be having latent iron deficiency (LID). In such situations the ferritin analysis will show low levels.

Correcting iron deficiency hair loss

In most of the cases of deficiency, taking food rich in the mineral and also taking supplements under the advice of a doctor may resolve iron deficiency induced hair loss. Heme iron is the most readily absorbed form and clam, red meat, kidney, liver, spleen, poultry and fish are rich sources. Green leafy vegetables, soybeans, lentils, legumes and dry fruits are rich non-heme sources. Oxalates, phytic acid and tannin present in plant foods bind to iron in the gut to form insoluble complexes, reducing the bioavailability.

Oral supplements such as ferrous sulfate, ferrous gluconate, or amino acid chelate tablets are prescribed to treat anemia. To treat chronic anemia, physician may recommend blood transfusion.
The supplements must be taken only under a doctor's guidance. Iron overdose can have serious health consequences.
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Reference:
1.Rushton DH. Nutritional factors and hair loss. Clin Exp Dermatol. 2002 Jul;27(5):396-404.
2.Trost LB, Bergfeld WF, Calogeras E. The diagnosis and treatment of iron deficiency and its potential relationship to hair loss. J Am Acad Dermatol. 2006 May;54(5):824-44.
3.Moeinvaziri M, Mansoori P, Holakooee K, Safaee Naraghi Z, Abbasi A. Iron status in diffuse telogen hair loss among women. Acta Dermatovenerol Croat. 2009;17(4):279-84.
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Current topic in natural skin care: Iron for hair growth - Iron deficiency hair loss.