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choma
Trachoma
Tr a c hom a is a highly c onta giou s ke r a toc onju nc tiv itis d u e to Chlamydia trachomatis.
The
d is e a s e is e nd e m ic in the p oor e s t r u r a l a r e a s of A fr ic a , A s ia , C e ntr a l a nd
S ou th A m e r ic a
a nd the M id d le E a s t.
Infe c tion is u s u a lly fir s t c ontr a c te d e a r ly in c hild hood b y d ir e c t or ind ir e c t c onta c t
(d ir ty
ha nd s , c onta m ina te d tow e ls , flie s ). In the a b s e nc e of hygie ne a nd e ffe c tiv e
tr e a tm e nt, the
infla m m a tion inte ns ifie s w ith s u c c e s s iv e infe c tions , c a u s ing s c a r s a nd
d e for m itie s on the
u p p e r ta r s a l c onju nc tiv a . The r e s u lting ingr ow ing e ye la s he s (tr ic hia s is ) c a u s e
c or ne a l
le s ions follow e d b y p e r m a ne nt b lind ne s s , u s u a lly in a d u lthood .
The W H O c la s s ifie s tr a c hom a into 5 s ta ge s . E a r ly d ia gnos is a nd tr e a tm e nt of
fir s t s ta ge s
is e s s e ntia l to a v oid the d e v e lop m e nt of tr ic hia s is a nd a s s oc ia te d
c om p lic a tions .
Clinical features
S e v e r a l s ta ge s c a n oc c u r s im u lta ne ou s ly:
– S ta ge I: tr a c hom a tou s infla m m a tion - follic u la r (TF )
P r e s e nc e of fiv e or m or e follic le s in the u p p e r ta r s a l c onju nc tiv a . F ollic le s a r e
w hitis h,
gr e y or ye llow e le v a tions , p a le r tha n the s u r r ou nd ing c onju nc tiv a .
– S ta ge II: tr a c hom a tou s infla m m a tion - inte ns e (TI)
The u p p e r ta r s a l c onju nc tiv a is r e d , r ou gh a nd thic ke ne d . The b lood v e s s e ls ,
nor m a lly
v is ib le , a r e m a s ke d b y a d iffu s e infla m m a tor y infiltr a tion or follic le s .
– S ta ge III: tr a c hom a tou s s c a r r ing (TS )
F ollic le s d is a p p e a r , le a v ing s c a r s : s c a r s a r e w hite line s , b a nd s or p a tc he s in
the ta r s a l
c onju nc tiv a .
– S ta ge IV : tr a c hom a tou s tr ic hia s is (TT)
D u e t o m u lt ip le s c a r s , t h e m a r gin of t h e e ye lid t u r n s in w a r d s ( e n t r op ion ) ;
the
e ye la s he s r u b the c or ne a a nd c a u s e u lc e r a tions a nd c hr onic infla m m a tion.
– S ta ge V : c or ne a l op a c ity (C O )
C or ne a gr a d u a lly los e s its tr a ns p a r e nc y, le a d ing to v is u a l im p a ir m e nt a nd
Trachoma
Tr a c hom a is a highly c onta giou s ke r a toc onju nc tiv itis d u e to Chlamydia trachomatis.
The
d is e a s e is e nd e m ic in the p oor e s t r u r a l a r e a s of A fr ic a , A s ia , C e ntr a l a nd
S ou th A m e r ic a
a nd the M id d le E a s t.
Infe c tion is u s u a lly fir s t c ontr a c te d e a r ly in c hild hood b y d ir e c t or ind ir e c t c onta c t
(d ir ty
ha nd s , c onta m ina te d tow e ls , flie s ). In the a b s e nc e of hygie ne a nd e ffe c tiv e
tr e a tm e nt, the
infla m m a tion inte ns ifie s w ith s u c c e s s iv e infe c tions , c a u s ing s c a r s a nd
d e for m itie s on the
u p p e r ta r s a l c onju nc tiv a . The r e s u lting ingr ow ing e ye la s he s (tr ic hia s is ) c a u s e
c or ne a l
le s ions follow e d b y p e r m a ne nt b lind ne s s , u s u a lly in a d u lthood .
The W H O c la s s ifie s tr a c hom a into 5 s ta ge s . E a r ly d ia gnos is a nd tr e a tm e nt of
fir s t s ta ge s
is e s s e ntia l to a v oid the d e v e lop m e nt of tr ic hia s is a nd a s s oc ia te d
c om p lic a tions .
Clinical features
S e v e r a l s ta ge s c a n oc c u r s im u lta ne ou s ly:
– S ta ge I: tr a c hom a tou s infla m m a tion - follic u la r (TF )
P r e s e nc e of fiv e or m or e follic le s in the u p p e r ta r s a l c onju nc tiv a . F ollic le s a r e
w hitis h,
gr e y or ye llow e le v a tions , p a le r tha n the s u r r ou nd ing c onju nc tiv a .
– S ta ge II: tr a c hom a tou s infla m m a tion - inte ns e (TI)
The u p p e r ta r s a l c onju nc tiv a is r e d , r ou gh a nd thic ke ne d . The b lood v e s s e ls ,
nor m a lly
v is ib le , a r e m a s ke d b y a d iffu s e infla m m a tor y infiltr a tion or follic le s .
– S ta ge III: tr a c hom a tou s s c a r r ing (TS )
F ollic le s d is a p p e a r , le a v ing s c a r s : s c a r s a r e w hite line s , b a nd s or p a tc he s in
the ta r s a l
c onju nc tiv a .
– S ta ge IV : tr a c hom a tou s tr ic hia s is (TT)
D u e t o m u lt ip le s c a r s , t h e m a r gin of t h e e ye lid t u r n s in w a r d s ( e n t r op ion ) ;
the
e ye la s he s r u b the c or ne a a nd c a u s e u lc e r a tions a nd c hr onic infla m m a tion.
– S ta ge V : c or ne a l op a c ity (C O )
C or ne a gr a d u a lly los e s its tr a ns p a r e nc y, le a d ing to v is u a l im p a ir m e nt a nd
