الفهرس 
Alopecia AreataOnly 14 pages are availabe for public view
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Abstract
Alopecia areata is a common type of hair loss or alopecia in
humans. The exact pathophysiology of AA is currently unknown.
Mitochondria have retained their own genome; mtDNA that is
essential for oxidative phosphorylation. Emerging evidence strongly
suggests that the proportion of mutated mtDNA copies is not the only
determinant of disease but that also the absolute copy number matters.
This study aimed to study mitochondrial DNA copy number in
patients with AA and healthy controls and to compare the results with
the available clinical data.
This is a case-control study that was performed at the
Dermatology, Andrology, and STDs,Department of Clinical
Biochemistry & Molecular Diagnostics, National Liver Institute. The
study included 05 patients with AA who were collected consequently
from the Outpatient Clinic of the Dermatology and Andrology, and
STDs , Menoufia University Hospitals. Additional 50 age and sex
matched normal healthy individuals were included as a control group.
Cases were subjected to full history taking, clinical examination
including detailed deramtologic clinical examination of scalp, nails
and glabrous skin. Assessment of disease severity was done by SALT
score. Cases were classified according to the Kavak’s classification
into mild, moderate, and severe.
Laboratory examination included DNA Extraction, PCR
amplification and mtDNA quantification using the suitable kits
according to the manufacturer instructions.
Summary
70
In this study, cases were 43 (86 %) males and 7 (14%) females.
Their age ranged from 20 to 45 years with 30.84± 8.06 years as X
±SD value. Control subjects were 42(84 %) males and 8 (16%)
females .Their age ranged from 20 to 45 years with 30.4± 6.7 as X
±SD value. There were no significant differences between cases and
controls regarding age and sex (p˃ 0.05 for both).
Regarding clinical data of the studied cases, onset of the disease
was sudden in 24 (48%) cases and was gradual in 26 (52%) cases. 17
(34%) cases had stationary course while 33 (66%) cases had
progressive course. Duration of disease ranged from 1 to 24 months
with 5.57± 5.60 months as X± SD. History of exposure to stressful
events was positive in 31 (62%) cases and was negative in 19 (38%)
cases. 12 (24%) cases were with positive family history of alopecia
areata and 38 (76%) cases had negative family history of alopecia
areata. Site of lesion was in scalp in all (100%) cases.
SALT score ranged from 10 to 100 with 22.77± 34.18 as X± SD
value. According to kavak’s classification; 25 (50%) cases had mild
AA, 15 (30%) cases had moderate AA and 10 (20%) cases had severe
AA.
There was statistically significant increase in mitochondrial DNA
copy number level in cases than controls (U= 14, p<0.001). There was
non-significant relationship between mean expression level of
mitochondrial DNA copy number and clinical data of the studied
cases. There was significant positive correlation between mean
expression level of mitochondrial DNA copy number and SALT score
(r=0.622, p=0.001).
Summary
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With cut off value > 1.619; there was a significant validity of
prediction (P-value < 0.001) of mitochondrial DNA copy number to
diagnose cases (N=50) of AA from controls (N=50) with sensitivity
and specificity of 96% and 98%, respectively.
By using ROC curve analysis, mitochondrial DNA copy number
expression can diagnose mild cases of AA from moderate cases with
sensitivity and specificity of 93.3% and 94.2%, respectively when the
cutoff point was > 1.36 and p value 0.007.
By using ROC-curve analysis, mitochondrial DNA copy number
expression can diagnose moderate cases of AA from severe cases with
sensitivity and specificity 80% and 86.67%, respectively, when the
cutoff point was > 2.94, with a statistically high significant p value
(p<0.001).
By using ROC-curve analysis, mitochondrial DNA copy number
expression can diagnose mild cases of AA from severe with sensitivity
and specificity of 80% and 88%, respectively, when the cutoff point
was > 3.13, with a statistically high significant p value (p<0.001).