Hair loss in dogs
December 30th, 2009N Z Vet J. 2009;57:170
Black-hair follicular dysplasia in a New Zealand Huntaway Dog.
Munday JS, French AF, McKerchar GR.
A 6-year-old intact male dog had slowly progressive hair loss first observed at 12 weeks of age. ... Patchy hair loss was confined to the black-haired areas of the body, and was most evident on the head and dorsum of the body; tan-haired areas of skin appeared normal. Histological examination of black-haired skin revealed distended melanocytes and large aggregates of melanin within, and surrounding, the hair follicles and the epidermis. The clinical and histological findings were consistent with black-hair follicular dysplasia (BHFD). ... This is the first report of BHFD in a dog in New Zealand, and is the first report in a Huntaway. The most significant effect of BHFD is a predisposition to follicular plugging and secondary bacterial skin infections. Due to the hereditary nature of the follicular dysplasias, breeding from affected dogs should be discouraged. snip
Edited for hair loss treatment blog
Eyelid pigment implantation
October 23rd, 2009Arch Ophthalmol. 1985;103(10):1515
Clinicopathologic correlate of a fresh eyelid pigment implantation.
Tse DT, et al
An eyelid with freshly applied black eyeliner pigment was examined histologically. X-ray microanalysis of the pigment suspension from the manufacturer's vial indicated that its composition was 98% iron and 2% titanium. Transmission electron microscopic examination disclosed that particles were in the extracellular matrix; intracellular particles were not seen. By light microscopy, implant material was detected in various levels of the dermis and was found in dermal lymphatics as well as within and surrounding a hair follicle. Our study suggests that systemic exposure to the implant material is possible and offers explanations for permanent eyelash hair loss, which we have seen following this procedure.
Hair-loss from alopecia congenita.
October 21st, 2009J Am Acad Dermatol. 1980;3:623
Analysis of hair from alopecia congenita.
Baden HP, Kubilus J.
Two patients with hair loss due to alopecia congenita had short vellus hairs of the scalp but some apparently normal-sized hairs in other areas. Both fibrous and matrix proteins were detected in the scalp hairs by polyacrylamide gel electrophoresis (PAGE), and x-ray diffraction analysis revealed a normal alpha pattern. Amino acid analysis showed a decreased cystine content suggesting a quantitative or qualitative change in the matrix component. Scanning electron microscopic examination revealed pits and bulges in the cuticle cells which may be related to wearing a wig. The data suggest a defect in the development of the follicle rather than an abnormality in a component of the hair.
Diagnosis and Treatment of male pattern hair loss
October 6th, 2009Am Fam Physician. 2009 Aug 15;80(4):356-62
Diagnosing and treating male pattern hair loss.
Mounsey AL, Reed SW.
Physicians should be careful not to underestimate the emotional impact of hair loss for some patients. Patients may present with focal patches of hair loss or more diffuse hair loss, which may include predominant hair thinning or increased hair shedding. Focal hair loss can be further broken down into scarring and nonscarring. Scarring alopecia is best evaluated by a dermatologist. The cause of focal hair loss may be diagnosed by the appearance of the patch and examination for fungal agents. A scalp biopsy may be necessary if the cause of hair loss is unclear. Alopecia areata presents with smooth hairless patches, which have a high spontaneous rate of resolution. Tinea capitis causes patches of alopecia that may be erythematous and scaly. Male and female pattern hair losses have recognizable patterns and can be treated with topical minoxidil, and also with finasteride in men. Sudden loss of hair is usually telogen effluvium, but can also be diffuse alopecia areata. In telogen effluvium, once the precipitating cause is removed, the hair will regrow.
Canine hypothyroidism and hair loss
October 4th, 2009J Am Vet Med Assoc. 1980 Dec 1;177(11):1117-22.
Canine hypothyroidism: a retrospective study of 108 cases.
Nesbitt GH, Izzo J, Peterson L, Wilkins RJ.
Hypothyroidism, defined as a serum concentration of less than 70 ng of triiodothyronine (T3)/dl or less than 1.5 microgram of thyroxine (T4)/dl, or both, was diagnosed in 108 dogs by means of radioimmunoassay techniques. Both T3 and T4 values were determined in 96 dogs. Both values were low in approximately 50% (47/96) of the hypothyroid dogs; 25% (24/96) were T3 hypothyroid (low T3, normal T4), and 26% (25/96) were T4 hypothyroid (normal T3, low T4). The T3 values varied markedly between animals. Common clinical signs were hair loss, changes in coat (dryness, dullness, dandruff, scales, coarseness, and slow hair regrowth), hyperpigmentation, and pyoderma. Doberman Pinschers, Great Danes, Poodles, Schnauzers, Irish Setters, and Boxers accounted for 50% (54/108) of the hypothyroid dogs. Therapy consisted of T4, T3, or combination T3 and T4 replacement. A good clinical response was observed with T4 replacement in 40.4% (19/47) within 2 months and in 21.3% (10/47) within 5 months. A poor clinical response was observed in 25.5% (12/47) after 6 months of therapy. Posttherapeutic evaluation was based on peak serum concentrations of T3 and T4, pretreatment (basal) thyroid hormone values, type of replacement therapy, dosage and time of sampling after treatment, concurrent clinical problems, and, most important, clinical response to thyroid replacement therapy.