167 / 280
The Pediatric Infectious Disease Journal •
Volume 33, Number 10, October 2014
Chronic Sinusitis
© 2014 Lippincott Williams &Wilkins
www.pidj.com|
polymicrobial infections. An increase in the isolation of
Prevotella
spp. was noted in the post-PCV13 period (
P
= 0.02) among patients
with pneumococcal isolates.
None of the patients developed intracranial complica-
tions. Two patients were treated for allergic fungal sinusitis and
pneumococcal (serotype 10 and 15C) sinusitis with antibiotics
and steroids. One patient (serotype 23A) developed mastoiditis
3 months after completing antibiotic therapy for sinusitis. Seven
patients had a second episode of pneumococcal sinusitis during
the study period; all of them underwent repeat ESS and intraop-
erative cultures were obtained. Data for the pneumococcal sero-
type for the second episode were not available in 3 patients. None
of the other 4 patients had the same pneumococcal serotype that
was isolated during the first surgical procedure. The most common
prescribed antibiotics post-surgery were cephalosporins (46%)
and amoxicillin-clavulanate (17%).
DISCUSSION
Our study revealed important changes in the epidemiology
of
S. pneumoniae
among children with chronic sinusitis after the
introduction of PCV13 in 2010. The proportion of cases of chronic
sinusitis attributable to
S. pneumoniae
showed a significant decline
in the 3 years after the introduction of PCV13. Isolation of PCV13
serotypes from children with chronic sinusitis also decreased sig-
nificantly, mostly related to a substantial decrease of serotype 19A.
In our study, the overall isolation rate of
S. pneumoniae
was
14%. This result is similar to previous studies from Brook et al
2
and Merino et al
16
who reported a pneumococcal isolation rate of
13% among adolescents and adults with chronic sinusitis during
1987–2004 and pre-PCV7 period, respectively. However, Tinkel-
man et al
4
reported a higher pneumococcal isolation rate of 23%
among young children (mean age 4.9 years) with chronic sinusitis
before the introduction of PCVs; this rate is similar to our results
(22%) from the pre-PCV13 period, which suggests that
S. pneu-
moniae
might play a more important role in chronic sinusitis in
younger children.
Despite a similar overall isolation rate of
S. pneumoniae
to studies conducted in the pre- and early post-PCV7 period, we
demonstrated a decrease of 13% (
P
< 0.0001) in the proportion
of chronic sinusitis cases attributable to
S. pneumoniae
after the
introduction of PCV13. We also found that the proportion of
chronic sinusitis cases because of PCV13 serotypes decreased 31%
(
P
= 0.003) in the post-PCV13 period, which is consistent with the
impact of PCV13 in invasive pneumococcal disease in US chil-
dren.
14,17
Our findings also provide evidence of indirect protection
of PCV13 given the substantial decline in chronic sinusitis attribut-
able to
S. pneumoniae
despite an incomplete vaccination rate. A
recent study reported a 50% decline in nasopharyngeal coloniza-
tion by PCV13 serotypes in non-PCV13 immunized children in
Massachusetts by 2012.
18
Pneumococcal serotype 19A was described as the most com-
mon serotype isolated from children with invasive pneumococcal
disease
13
as well as chronic sinusitis
12
after the introduction of PCV7.
In our study, we demonstrated a pronounced decline of serotype 19A
(38% vs. 11%; −27%
P
= 0.007) after the introduction of PCV13.
Moreover, serotype 19A was not responsible for any of the cases of
chronic sinusitis in 2013. Non-PCV13 serotypes represented 86% of
all the isolates in the post-PCV13 period; and serotype 15C became
the most common serotype during the same period. Similarly, Lee et
al
19
evaluated rates of pneumococcal colonization in children after
PCV13 introduction and reported that serotype 15B/C has emerged
as the most common isolate, whereas serotype 19A remained the
second most common serotype in 2011. Despite these changes in
serotype distribution, we did not observe an early emergence of
replacement non-PCV13 serotypes. A significantly greater number
of serotype 19A isolates showed high MIC for penicillin and ceftri-
axone than non-19A serotypes, as described in previous studies.
12,13
In our study, 18% of children with chronic sinusitis had
S. pneumoniae
-only infections; the remainder had polymicrobial
infections. Similar results among patients with chronic sinusitis
have been described.
10,12
Results from an AOM study in children
described that
S. pneumoniae
-only infections were associated with
serotypes identified as having higher disease potential, whereas
mixed
S. pneumonia
e and
H. influenzae
infections were associ-
ated with serotypes identified as having low disease potential.
20
Similarly, Xu et al
21
reported when
S. pneumoniae
co-colonized
the nasopharynx with
H. influenzae
, the latter predominated over
all
S. pneumoniae
strains except for serotype 19A to cause AOM.
TABLE 1.
Serotype Distribution of Pneumococcal
Isolates Recovered From Children Undergoing
Endoscopic Sinus Surgery
Pre-PCV13 Post-PCV13 Total
P
PCV13
19A
21
4
25
0.0074
19F
2
0
2
NS
3
2
1
3
NS
Non-PCV13
35B
7
5
12
NS
15C
3
6
9
NS
6C
4
4
8
NS
23A
5
2
7
NS
11
1
4
5
NS
15B
2
3
5
NS
15A
1
2
3
NS
22F
2
0
2
NS
23B
1
1
2
NS
33F
0
2
2
NS
10
1
0
1
NS
16
0
1
1
NS
17
1
0
1
NS
21
0
1
1
NS
33A
1
0
1
NS
34
1
0
1
NS
Pre-PCV13 versus post-PCV13 periods.
NS, no significant.
TABLE 2.
Other Organisms in Addition to
S.
pneumoniae
Isolated From Children Undergoing
Endoscopic Sinus Surgery
Species
Pre-PCV13 Post-PCV13 Total
P
Nontypeable
H. influenzae
28
19
47 NS
Moraxella catarrhalis
22
11
33 NS
S. aureus
7
3
10 NS
Fungal species*
6
1
7 NS
Haemophilus
parainfluenzae
3
2
5 NS
Prevotella
spp.
0
4
4 0.02
Pseudomonas
aureginosa
3
1
4 NS
Coagulase-negative
Staphylococcus
3
0
3 NS
Stenotrophomonas
maltophilia
2
0
2 NS
Other organisms†
5
1
6 NS
*Two isolates each of
Candida
spp. and
Aspergillus flavus
. One isolate each of
Fusobacterium
spp.,
Bipolaris
spp. and
Curvularia
spp.
†One isolate each of
Escherichia coli
,
Klebsiella pneumoniae
,
Enterobacter cloacae
,
Corynebacterium
spp.,
Neisseria
spp. and alpha-hemolytic
Streptococcus
spp.
145