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Capnocytophaga canimorsus blebitis: case report and review of literature


Abstract and Figures

Background Capnocytophaga canimorsus is a facultative anaerobic, slow-growing, capnophilic, Gram-negative bacillus, that is commonly found in the microflora of canine and feline oral cavities. Capnocytophaga infections are an emerging zoonotic disease that can cause fatal systemic infections in immunocompromised individuals. Localized ocular Capnocytophaga infections, including keratitis, blepharitis, and endophthalmitis, can lead to severe eye threatening situations. To our knowledge, there is currently no documented case of Capnocytophaga canimorsus blebitis with bleb perforation after trabeculectomy. Case presentation Our case report and literature review features a novel case of Capnocytophaga blebitis that occurred after trabeculectomy, associated with close dog contact (i.e. face licking). The patient had underwent trabeculectomy 10 years prior and presented with conjunctival injection, perforated bleb, and hypotony. Overall, patient was medically treated subconjunctival vancomycin, gentamicin and moxifloxacin drops. Trabeculectomy revision was performed with good visual outcome. Bacterial cultures grew Capnocytophaga canimorsus . Conclusions We discuss the strategies for diagnosis, treatment, and common risk factors for ocular Capnocytophaga infections. At-risk patients with ocular infections should be asked about close contact with dogs and cats; and treated promptly with the proper antibiotic regimen.
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C A S E R E P O R T Open Access
Capnocytophaga canimorsus blebitis: case
report and review of literature
Michael C. Yang, John Ling and Sameh Mosaed
Background: Capnocytophaga canimorsus is a facultative anaerobic, slow-growing, capnophilic, Gram-negative
bacillus, that is commonly found in the microflora of canine and feline oral cavities. Capnocytophaga infections are
an emerging zoonotic disease that can cause fatal systemic infections in immunocompromised individuals.
Localized ocular Capnocytophaga infections, including keratitis, blepharitis, and endophthalmitis, can lead to severe
eye threatening situations. To our knowledge, there is currently no documented case of Capnocytophaga
canimorsus blebitis with bleb perforation after trabeculectomy.
Case presentation: Our case report and literature review features a novel case of Capnocytophaga blebitis that
occurred after trabeculectomy, associated with close dog contact (i.e. face licking). The patient had underwent
trabeculectomy 10 years prior and presented with conjunctival injection, perforated bleb, and hypotony. Overall,
patient was medically treated subconjunctival vancomycin, gentamicin and moxifloxacin drops. Trabeculectomy
revision was performed with good visual outcome. Bacterial cultures grew Capnocytophaga canimorsus.
Conclusions: We discuss the strategies for diagnosis, treatment, and common risk factors for ocular
Capnocytophaga infections. At-risk patients with ocular infections should be asked about close contact with dogs
and cats; and treated promptly with the proper antibiotic regimen.
Keywords: Capnocytophaga canimorsus, Blebitis, Trabeculectomy, Bleb perforation, Bleb-associated infections, Case
Pet ownership has many benefits, with some studies
reporting a lower risk of cardiovascular disease and mor-
tality with dog ownership [1]. This cohabitation also
comes with its own risks; half of all Americans will be
bitten at least once in their lifetime [2]. Capnocytophaga
canimorsus is commonly found in canine oral micro-
flora, and less commonly in cats. In certain studies, C.
canimorsus could be cultured from oral secretions of ap-
proximately 26% of dogs and 18% of cats [3]. Recent re-
ports have shown the prevalence to be up to 74% of
dogs [4]. C. canimorsus can cause a wide variety of infec-
tions, with a majority being systemic infections and less
than 10% being localized infections [5]. Many of these
localized infections have been ocular; reports include
blepharitis, keratitis, and endophthalmitis [68]. How-
ever, to our knowledge, there has not yet been a re-
ported case of blebitis linked to C. canimorsus.We
present a case of C. canimorsus blebitis with bleb perfor-
ation, which highlights the virulence of C. canimorsus
and the need for pet owners with predisposing risk fac-
tors to be vigilant of ocular exposures.
Case presentation
An 81-year-old man was referred by an outside ophthal-
mologist with bacterial blebitis and perforated bleb, 10
years after trabeculectomy. Patients medical history was
unremarkable. His ocular history includes radial keratot-
omy, penetrating keratoplasty (PKP), and the
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* Correspondence:
Department of Ophthalmology, Gavin Herbert Eye Institute, University of
California, Irvine, CA 92697, USA
Yang et al. BMC Ophthalmology (2021) 21:59
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aforementioned trabeculectomy 10 years prior. Upon
presentation, patients exam was notable for significant
conjunctival injection, elevated cystic bleb, positive Sei-
dels test with significant flow, and intraocular pressure
of 4 mmHg (Fig. 1). Best corrected vision was 20/100.
Corneal exam revealed fine keratic precipitates (KP) and
evidence of PKP with mild haze around the periphery of
the graft. Anterior chamber exam revealed trace cell and
flare. Fundus exam was unremarkable except for cup-to-
disc ratio of 0.85. No cells seen in vitreous. Given exam
findings and concern for infection, patient was given
subconjunctival injection of vancomycin 25 mg and gen-
tamicin 20 mg. Conjunctival samples and scrapings were
sent for fungal and bacterial cultures. Patient was pre-
scribed a prolonged course of moxifloxacin drops; ini-
tially every 1 h and eventually tapered to four times a
day. Prednisolone acetate drops were added, and the pa-
tient was monitored regularly in clinic with improve-
ment to his clinical condition.
Two weeks after initial presentation, trabeculectomy
revision was performed involving closure of the bleb, ex-
cision of necrotic tissue and scleral patch graft (Fig. 2).
Several months after surgery, patient continued to be
Seidels negative with normal intraocular pressure, and
best corrected vision was 20/70 (Fig. 3). Per standard
protocol at our institution, samples were plated on sheep
blood, chocolate, Mac Conkey agar, Brucella agar,
phenyl ethyl alcohol agar, split plate (Bacteroides Bile
Esculin, Laked Brucella agar with Kanamycin and
Vancomycin), and thioglycolate. Given initial appearance
as a rare bacillus species, cultures were sent to County
of Orange, Health Care Agency, Public Health
Laboratory for final identification of C. canimorsus spe-
cies. Further details regarding identification and isolation
were unavailable from the Public Health Laboratory
however, C. canimorsus has been known to grow on 5%
sheep blood or chocolate agar in 510% CO
at 37 C [5].
The diagnosis of C. canimorsus was initially suggested
by appearance on Gram stain at our institution and final
identification was made at aforementioned laboratory
(Fig. 4). Further confirmation of C. canimorsus was ob-
tained through DNA sequencing from an outside labora-
tory. The diagnosis of Capnocytophaga canimorsus was
also confirmed independently by the referring ophthal-
mologists cultures and testing. Fungal cultures were
negative. Upon further questioning, patient revealed that
he had a Dalmatian dog with poor dentition that fre-
quently licked his face.
Discussion and conclusion
Capnocytophaga canimorsus is a Gram-negative bacillus
that is capnophilic, a facultative anaerobe, and belongs
in the Bacteroidetes phylum. It was originally named
CDC group dysgonic fermenter 2 (DF-2), with articles
published in the 1980s referring to Capnocytophaga
canimorsus as DF-2. The first human infection was re-
ported in 1976, and there has only been approximately
500 reported cases worldwide [9]. This is likely an
underreported figure given that C. canimorsus is notori-
ously difficult to culture, and can also result in subclin-
ical infections [10]. C. canimorsus can be transmitted
through bites, scratches, and close animal contact (e.g.
licking) [5].
With recent advances in ribosomal DNA sequencing,
some researchers have proposed splitting Capnocyto-
phaga canimorsus into two different species. The pro-
posed name of the subclinical strain is Capnocytophaga
canis, and maintaining the same name of Capnocyto-
phaga canimorsus for the clinically symptomatic strain.
However, recent case reports have isolated C. canis from
patients with sepsis [11]. The strains that are harmful to
humans all grow in heat-inactivated human serum, de-
glycosylate IgM and are cytochrome-oxidase positive [4].
Healthy, immunocompetent individuals are typically not
susceptible to overt systemic C. canimorsus infections.
However, at-risk individuals (e.g. immunocompromised,
alcoholics, splenectomized patients) can have systemic
C. canimorsus infections like endocarditis, meningitis,
and even fatal bacteremia leading to multi-organ system
failure [1215].
Localized C. canimorsus infections have been mostly
identified in the eye; keratitis being the most common
presentation. Capnocytophaga keratitis is an aggressive
cornea infection; in a study of ten patients, 50% required
enucleation and 30% required corneal transplant [16].
Given its capnophilic nature, Capnocytophaga has a
Fig. 1 Capnocytophaga blebitis, preoperative clinical image.
Significant injection, cystic bleb, with associated bleb leakage
Yang et al. BMC Ophthalmology (2021) 21:59 Page 2 of 5
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predilection for the deeper layers of the corneal stroma.
Patients often present with corneal edema, endothelial
lesions, ring-shaped infiltrates, and corneal perforation.
Like our presented case, patients with Capnocytophaga
keratitis report frequent and close interactions with dogs
(e.g. face licking) [17]. Patients susceptible to Capnocyto-
phaga keratitis are often immunocompromisedfor
Fig. 2 Capnocytophaga blebitis, intraoperative images of trabeculectomy revision. aSeidel positive, indicating bleb leakage. bLimbus dissection.
cFlap closure with 100 Prolene suture, interrupted. dPlacement of scleral patch graft secured with 80 Vicryl sutures. eConjunctival closure
with 100 Vicryl sutures, running. fWatertight closure confirmed with Seidel negative
Fig. 3 Capnocytophaga blebitis, 4 weeks postoperative clinical
image. Status post bleb closure, excision of necrotic tissue and
scleral patch graft. No bleb leakage, dissolving running suture
visualized at limbus
Fig. 4 Capnocytophaga canimorsus Gram stain image. Gram
negative rods, fusiform cells generally 13μm in length. Sample
culture image obtained with permission from Microbe-Canvas team
Yang et al. BMC Ophthalmology (2021) 21:59 Page 3 of 5
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
example, status post bone marrow transplant, or rituxi-
mab infusions. Professions that are regularly exposed to
canine and feline mouths (i.e. veterinarians) are also at
risk [7]. Topical clindamycin has been used with good
clinical results in some patients [7,16,17]. Some clini-
cians have also used oral clindamycin to achieve higher
levels of antibiotics in the anterior chamber and deeper
layers of the cornea where Capnocytophaga resides.
The reported incidence of bleb-associated infections
(BAI) range from 1.5 to 4.8% at 5 years follow up. BAIs
range from stage I with no cell in the anterior chamber
and little to no visual impairment to stage IIIB with cell
in the anterior chamber and vitreous with an obscured
view of the fundus [18]. Early BAI occurs within the first
post-operative month, and late BAI occurs after the first
month. Our case of Capnocytophaga blebitis is a late
BAI and stage II (cell in anterior chamber, no cell in vit-
reous). Diagnostic workup can include aqueous/vitreous
stain and culture, polymerase chain reaction (PCR),
biome representational in silico karyotyping (BRiSK), or
metagenomic deep sequencing (MDS) [1618]. The
most commonly isolated microorganisms in early onset
BAI is coagulase negative Staphylococcus, and late onset
BAI is Streptococcus. There is currently no consensus on
the most effective treatment for BAI. However, com-
monly used treatment regimens are fortified aminoglyco-
sides (e.g. tobramycin (14 mg/mL) with vancomycin (q30
min) or 4th generation fluoroquinolone (q1 hour) [19].
These antibiotics broadly cover Gram-negative and
Gram-positive microorganisms. Of note, Capnocytopha-
gassusceptibility to aminoglycosides and vancomycin
varies widely between studies; but is typically susceptible
to clindamycin, penicillin, cephalosporin, imipenem, and
beta-lactamase inhibitor combinations [7,20]. Our pa-
tient was initially treated with subconjunctival vanco-
mycin and gentamicin; and eventually shifted to a
prolonged course of topical moxifloxacin with treatment
success. Subconjunctival antibiotics are not routinely ad-
ministered; however, our patient was elderly and the typ-
ical regimen of q30 min eyedrops of vancomycin and
aminoglycoside was not possible. Additionally, given the
urgency of acute blebitis and the importance of prompt
administration of antibiotics, we opted for a broad
spectrum approach with vancomycin and gentamicin be-
fore culture sensitivities were available. Given its high li-
pophilicity, topical moxifloxacin achieves high
intraocular concentrations in aqueous humor and con-
junctiva. Moxifloxacin covers broadly for Gram-negative,
Gram-positive and atypical pathogens [18].
Capnocytophaga canimorsus is a member of the com-
plex microflora of canine and feline oral cavities. In im-
munocompromised patients, C. canimorsus has been
known to cause severe systemic infections like
bacteremia and multi-organ failure. In rare cases, C.
canimorsus can cause eye-threatening ocular infections
ranging from keratitis to endophthalmitis. Our novel
case of Capnocytophaga blebitis contributes to the
scarce clinical information available regarding ocular
Capnocytophaga infections. At-risk patients with ocular
infections should be asked about close contact with dogs
and cats; and treated promptly with the proper antibiotic
PKP: Penetrating keratoplasty; KPP: Keratic precipitates; CDCP: Centers for
Disease Control; DF-2P: Dysgonic fermenter 2; BAIP: Bleb-associated
infections; PCRP: Polymerase chain reaction; BRiSKP: Biome representational
in silico karyotyping; MDSP: Metagenomic deep sequencing
Thank you to Dr. Mosaed and Dr. Ling for all their support. Special thanks to
the team at Microbe-Canvas for the generous contribution of the Gram stain
image of C. canimorsus.
MY drafted manuscript and performed literature review of related topics
including: C. canimorsus and blebitis treatment strategies. JL & SM significant
contributions in conception and acquisition of data, revision of manuscript,
as well as direct patient care involved in case. All authors read and approved
the final manuscript.
No financial support.
Availability of data and materials
Data sharing is not applicable to this article as no datasets were generated
or analyzed during the current study.
Ethics approval and consent to participate
Need for approval from ethics was waived.
Consent for publication
Written consent for the publication of identifying clinical/personal
information and images was obtained from the patient.
Competing interests
The authors declare that they have no competing interests.
Received: 23 December 2019 Accepted: 20 January 2021
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... BAE is further classified as early-or late-onset, with a cut-off point corresponding to one month postoperatively [4,5]. The filtering bleb is purportedly recognized as the portal entry of causative pathogens such as Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus species, and Haemophilus influenza, which are the most common pathogens associated with BRIs, but in recent years, there have been multiple case reports describing rarer pathogens [6][7][8][9][10][11]. The goal of this review was to ...
... Late-onset BRE are causatively related not only to gram-positive cocci, but also to pathogens such as Haemophilus sp., Serratia sp., Enterococcus sp. [6,11,59,60]. In a 14-year retrospective consecutive case series conducted by Jacobs et al., positive cultures were correlated with poorer VA outcomes [18]. ...
... Rare and uncommon microorganisms, causatively related to both blebitis and endophthalmitis, have also been reported in some case reports and case series. In a recent case report, Yang et al. referred to a patient with late-onset stage II blebitis with concomitant bleb perforation, ascribed to Capnocytophaga canimorsuss, an anaerobic gram-negative bacillus, transmitted by his canine saliva [11]. Streptococcus mitis presents with a moderate frequency concerning BRIs and we have reported 17 culture-proven cases. ...
Full-text available
At the present time, as newer techniques and minimally invasive procedures gain popularity among anterior segment surgeons for regulating intraocular pressure, trabeculectomy still has a leading role in glaucoma surgery. Trabeculectomy retains a highly successful and safe profile; however, one of the major complications includes bleb-related infections (BRIs). To date, the most common pathogens remain Gram-positive cocci, but the list of pathogens that have been identified in the literature includes more than 100 microorganisms. Because antibiotic use is more widespread than ever before and our ability to identify pathogens has improved, the pathogen spectrum will broaden in the future and more pathogens causing BRIs will be described as atypical presentations. The scope of this review was to identify all pathogens that have been described to cause bleb-related infections to date, as well as focus on the risk factors, clinical presentation, and various available diagnostic tools used for an appropriate diagnostic workup.
Background Capnocytophaga canimorsus infections are a rare consequence of dog or cat bites, scratches or general exposure. Their non-specific presenting features and the technical difficulties culturing the bacterium render it a challenging diagnosis. Case report This case report describes a case of Capnocytophaga canimorsus, in an apparently immunocompetent 58-year-old male, secondary to multiple dog bites and scratches. Following antibiotic therapy, surgical repair of his perforated gastric ulcer and a post-operative stay complicated by delirium he was discharged having made a complete recovery. Results Literature recognises embolic secondary to Capnocytophaga canimorsus infections however, to the best knowledge of the authors, this is the only reported case of pneumoperitoneum secondary to stress ulceration in a Capnocytophaga canimorsus septicaemia. In this case the identification of multiple dog bites and scratches only occurred retrospectively after Capnocytophaga canimorsus had been cultured. This indicates that these risk factors are not routinely screened for and highlights the importance of identifying such risk when attempting to delineate the cause of sepsis of unknown origin. Conclusion Whilst being the first case report of pneumoperitoneum secondary to a Capnocytophaga canimorsus infections, this case reports highlights its non-specific presenting features thus the importance of identifying animals bites and scratches when attempting to identify an infection of unknown origin.
Full-text available
Purpose: To report our experience with 2 cases of Capnocytophaga keratitis. Methods: This is a retrospective study of case reports. We present the clinical presentation, diagnosis, and treatment strategies of 2 patients who presented with Capnocytophaga keratitis. Results: Both patients had risk factors including systemic immune compromise and ocular trauma. Both patients had robust inflammatory keratitis with necrosis. Case 1 demonstrates identification of Capnocytophaga with traditional microbiologic techniques. Case 2 demonstrates the use of unbiased metagenomic deep sequencing for identification of this unusual corneal pathogen. Conclusions: Capnocytophaga is a rare and aggressive infection. Even when traditional culture identifies the pathogen rapidly, keratitis can progress to perforation. In cases of severe keratitis in which traditional culture methods are unrevealing, metagenomic deep sequencing has potential to provide actionable diagnoses.This is an open access article distributed under the Creative Commons Attribution License 4.0 (CCBY), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Full-text available
Capnocytophaga canimorsus (CC) belongs to the family Flavobacteriaceae which physiologically occurs in the natural flora of the oral mucosa of dogs and cats. In patients with a compromised immune system, CC can induce a systemic infection with a fulminant course of disease. Infections with CC are rare, and the diagnosis is often complicated and prolonged. We describe a patient with a medical history of prior splenectomy who presented with an acute sepsis and disseminated intravascular coagulation (DIC) and was initially treated on Waterhouse–Friderichsen syndrome (WFS). After the patient had died despite forced treatment in the intermediate care unit, the differential diagnosis of CC was confirmed by culture of blood smears. Later on, a retrospective third-party anamnesis revealed that the patient had contact to his neighbour’s dog a few days before disease onset. In conclusion, patients with CC infection can mimic WFS and therefore must be included in the differential diagnosis, especially in patients with a corresponding medical history of dog or cat bites, scratches, licks, or simple exposure.
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Dogs may be beneficial in reducing cardiovascular risk in their owners by providing social support and motivation for physical activity. We aimed to investigate the association of dog ownership with incident cardiovascular disease (CVD) and death in a register-based prospective nation-wide cohort (n = 3,432,153) with up to 12 years of follow-up. Self-reported health and lifestyle habits were available for 34,202 participants in the Swedish Twin Register. Time-to-event analyses with time-updated covariates were used to calculate hazard ratios (HR) with 95% confidence intervals (CI). In single- and multiple-person households, dog ownership (13.1%) was associated with lower risk of death, HR 0.67 (95% CI, 0.65–0.69) and 0.89 (0.87–0.91), respectively; and CVD death, HR 0.64 (0.59–0.70), and 0.85 (0.81–0.90), respectively. In single-person households, dog ownership was inversely associated with cardiovascular outcomes (HR composite CVD 0.92, 95% CI, 0.89–0.94). Ownership of hunting breed dogs was associated with lowest risk of CVD. Further analysis in the Twin Register could not replicate the reduced risk of CVD or death but also gave no indication of confounding by disability, comorbidities or lifestyle factors. In conclusion, dog ownership appears to be associated with lower risk of CVD in single-person households and lower mortality in the general population.
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Capnocytophaga canimorsus are gram-negative bacteria living as commensals in the mouth of dogs and cats. C. canimorsus cause rare but life-threatening generalized infections in humans that have been in contact with a dog or a cat. Over the last years we collected 105 C. canimorsus strains from different geographical origins and from severe human infections or healthy dogs. All these strains were analyzed by 16S rDNA sequencing and a phylogenetic tree revealed two main groups of bacteria instead of one with no relation to the geographical origin. This branching was confirmed by the whole-genome sequencing of 10 strains, supporting the evidence of a new Capnocytophaga species in dogs. Interestingly, 19 out of 19 C. canimorsus strains isolated from human infections belonged to the same species. Furthermore, most strains from this species could grow in heat-inactivated human serum (HIHS) (40/46 tested), deglycosylate IgM (48/66) and were cytochrome-oxidase positive (60/66) while most strains from the other species could not grow in HIHS (22/23 tested), could not deglycosylate IgM (33/34) and were cytochrome-oxidase negative (33/34). Here, we propose to call Capnocytophaga canis (Latin: dog) the novel, presumably less virulent dog-hosted Capnocytophaga species and to keep the name C. canimorsus for the species including human pathogens.
Capnocytophaga canimorsus and Capnocytophaga cynodegmi, both commensal bacteria in the oral cavity of dogs and cats, are zoonotic pathogens. In particular, C. canimorsus causes sepsis and fatal septic shock. Recently, a novel Capnocytophaga species, C. canis, was isolated from the oral cavity of healthy dogs. C. canis was reported to be oxidase‐negative, thus considered to be avirulent in humans. In the present study, we found three clinical strains of C. canis from Japanese septic patients. All three strains, HP20001, HP33001, and HP40001, showed oxidase‐positive. Nucleotide sequence identities of the 16S rRNA gene of the three strains to the C. canimorsus type strain ATCC35979, C. cynodegmi type strain ATCC49044, and C. canis type strain LMG29146 were 96.9–97.0%, 96.9–97.0%, and 99.7–99.8%, respectively. Multi‐locus sequence analysis based on seven house‐keeping genes, dnaJ, fumC, glyA, gyrB, murG, trpB, and tuf, revealed that the oxidase‐positive C. canis strains isolated in Japan and oxidase‐negative strains of C. canis from the canine oral cavity in Switzerland were clustered in different genetic subgroups. These results indicate that the virulence of C. canis strains in humans is associated with oxidase activity.
Purpose: To describe a case of acute postoperative bacterial endophthalmitis because of Capnocytophaga canimorsus after cataract surgery, with probable contamination through salivary droplets of dog two days after the procedure. Methods: An 83-year-old woman who underwent uncomplicated cataract extraction with intraocular lens implantation, presented 12 days later with acute pain, redness, and vision loss in her left eye. Visual acuity was hand motion and clinical findings suggested the diagnosis of acute postoperative endophthalmitis. The patient underwent diagnostic vitrectomy, intravitreal ceftazidime/vancomycin injection and received oral moxifloxacin (400 mg/day). Two days later, she underwent complete pars-plana vitrectomy because of the absence of clinical improvement. Vitreous samples showed gram-negative bacterium on direct examination but cultures remained sterile, which prompted the realization of a broad-range bacterial polymerase chain reaction analysis. Results: Polymerase chain reaction on the vitreous sample detected C. canimorsus, a fastidious gram-negative bacterium of the oral canine flora. When asked for recent contact with dogs, the patient reported having proceeded to an intensive tooth care session for her dog at postoperative Day 2. Intravenous ceftriaxone (2 g/day) was added to the treatment. Anterior and posterior segment inflammation slowly resolved, and final visual acuity was 20/160. Conclusion: Although very rare, this complication suggests that patients undergoing ocular surgery should avoid contact with salivary secretions of pets during the early postoperative period. Diagnostic broad-range bacterial polymerase chain reaction is useful to detect unconventional or slow-growing agents in vitreous samples.
Trabeculectomy with antimetabolites is the most commonly performed surgery worldwide for glaucoma patients with progressive optic nerve head injury and visual field loss despite maximum pharmacologic intraocular pressure (IOP) lowering therapy. Trabeculectomy bleb-associated infections (BAI) remain one of the most feared early and long-term complications of trabeculectomy surgery because of their poor prognosis and variable response to antimicrobial therapy. Several studies have evaluated how surgical technique, conjunctival incision location, comorbid ocular pathology, concurrent medication use, and bleb morphology affect the risk of BAI. New surgical techniques and devices aim to achieve a similar IOP reduction profile to trabeculectomy while avoiding the presence of a conjunctival bleb. We provide a comprehensive review of studies evaluating risk factors for BAI after trabeculectomy and propose a diagnostic and therapeutic approach to BAI.
Bacterial meningitis is a disease with a high morbidity and mortality. It may be caused by the zoonotic pathogen Capnocytophaga canimorsus, which is part of the commensal oral flora in dogs and cats. We report three cases of C. canimorsus meningitis in a nationwide cohort study of bacterial meningitis patients and performed a review of the literature. Three episodes of C. canimorsus meningitis were identified in three patients included in a nationwide cohort study from 2006 through 2014. The calculated annual incidence was 0.03 per million adults. When combined with the literature, 33 patients were identified of which 28 were male (85%). The median age was 63 years, and 13 (42%) were immunocompromised, which consisted of alcoholism in 7 (21%). Animal contact could be established in 29 of 30 patients (93%) and consisted of dog bites in 22 of 29 (76%). One patient died (3%) and 8 had neurological sequelae upon discharge (25%), most often hearing loss (n = 6, 19%). Capnocytophaga canimorsus meningitis is associated with dog bites. Although mortality is relatively low, survivors often have neurological sequelae.
Newly named in 1989, Capnocytophaga canimorsus is a bacterial pathogen found in the saliva of healthy dogs and cats, and is transmitted to humans principally by dog bites. This review compiled all laboratory-confirmed cases, animal sources, and virulence attributes to describe its epidemiology, clinical features, and pathogenesis. An estimated 484 patients with a median age of 55 years were reported, two-thirds of which were male. The case-fatality rate was about 26 %. Its clinical presentations included severe sepsis and fatal septic shock, gangrene of the digits or extremities, high-grade bacteremia, meningitis, endocarditis, and eye infections. Predispositions were prior splenectomy in 59 patients and alcoholism in 58 patients. Dog bites before illness occurred in 60 %; additionally, in 27 %, there were scratches, licking, or other contact with dogs or cats. Patients with meningitis showed more advanced ages, higher male preponderance, lower mortality, and longer incubation periods after dog bites than patients with sepsis (p < 0.05). Patients with prior splenectomy presented more frequently with high-grade bacteremia than patients with intact spleens (p < 0.05). The organism possesses virulence attributes of catalase and sialidase production, gliding motility, cytotoxin production, and resistance to killing by serum complement due to its unique lipopolysaccharide. Penicillin is the drug of choice, but some practitioners prefer third-generation cephalosporins or beta-lactamase inhibitor combinations. C. canimorsus has emerged as a leading cause of sepsis, particularly post-splenectomy sepsis, and meningitis after dog bites.