Acinetobacter as a causative agent in preseptal cellulitis

Carbapenem-resistant Acinetobacter baumannii: Colonization, Infection and Current Treatment Options

Carbapenem-resistant Acinetobacter baumannii (CRAB) causes colonization and infection predominantly in hospitalized patients. Distinction between the two is a challenge. When CRAB is isolated from a non-sterile site (soft tissue, respiratory samples, etc.), it probably represents colonization unless clear signs of infection (fever, elevated white blood count, elevated inflammatory markers and abnormal imaging) are present. Treatment is warranted only for true infections. In normally sterile sites (blood, cerebrospinal fluid) the presence of indwelling medical devices (catheters, stents) should be considered when evaluating positive cultures. In the absence of such devices, the isolate represents an infection and should be treated. If an indwelling device is present and there are no signs of active infection, the device should be replaced if possible, and no treatment is required. If there are signs of an active infection the device should be removed or replaced, and treatment should be administered. Current treatments options and clinical data are limited. No agent or combination regimen has been shown to be superior to any other in randomized clinical trials. Ampicillin-sulbactam appears to have the best evidence for initial use. This is probably due to its ability to saturate penicillin-binding proteins 1 and 3 when given in high dose. Tigecycline when used should be given in high dose as well. Polymyxins are a treatment option but are difficult to dose correctly and have significant side effects. Newer treatment options such as eravacycline and cefiderocol have potential; however, currently there are not enough data to support their use as single agents. Combination therapy appears to be the best treatment option and should always include high-dose ampicillin-sulbactam combined with another active agent such as high-dose tigecycline, polymyxins, etc. These infections require a high complexity of skill, and an infectious disease specialist should be involved in the management of these patients.

An insight on management of odontogenic orbital infections: report of two cases

Odontogenic infections are common and very often spread to potential spaces of head and neck. The spread of such infection to adjacent maxillary sinuses or distant sites such as the orbits are a rare occurrence and may develop periorbital and orbital cellulitis. Unfortunately once orbital cellulitis and subsequently orbital abscess develops it can give rise to serious complications such as complete blindness or even more serious and life-threatening situations as cavernous sinus thrombosis, intracranial abscess or even death. Two cases are presented to demonstrate the differences between the two conditions and the necessary management in either case. This article provides an insight into the clinical behaviour of orbital infections of odontogenic origin with contemporary diagnostic and treatment modalities that will help in reducing morbidity and mortality associated with these conditions.

Acinetobacter junii as an aetiological agent of corneal ulcer

Rods of the Acinetobacter genus are present mainly in the external environment (e.g. water, soil) and in animals, while in humans they may comprise physiological flora. The main pathogenic species is Acinetobacter baumannii complex, which constitutes a common cause of nosocomial infections, particularly in patients with underlying diseases and risk factors (e.g. prior broad-spectrum antibiotic therapy, malignancy, central venous catheter, mechanical ventilation); however, infections of the eye caused by strains of Acinetobacter spp. are very rare. We report a unique case of community-acquired corneal ulcer caused by Acinetobacter non-baumannii (possibly A. junii), in a patient with no risk factors identified. The case highlights the need for obtaining a sample from the cornea for bacteriological culture in the case of suspected ophthalmic infection as identification of the pathogen, and assessment of its susceptibility profile enables proper antibiotic therapy, improves the outcome and may constitute an eyesight-saving management.

Pediatric subperiosteal orbital abscess secondary to acute sinusitis: a 5-year review

OBJECTIVE

Subperiosteal orbital abscesses (SPOAs) secondary to acute sinusitis are rare occurrences in the pediatric age group, more so in the neonatal period. Here, a rare case of SPOA in a 38-day-old newborn later drained via endoscopic sinus surgery is included also. This review describes the demographic data, clinical history, treatment, microbiology results, complications, and outcome.

METHODS

The admission records for all the patients who were admitted to the Pediatric Surgical Ward in Sarawak General Hospital, Kuching, Malaysia, between January 2004 and May 2009 were retrospectively reviewed. Records of patients who presented with preseptal cellulitis, orbital cellulitis, subperiosteal abscess (extraconal), orbital abscess (intraconal), and cavernous sinus thrombosis were closely studied. Ophthalmology consultations were obtained in all these cases. Ultimately, 3 patients having SPOA secondary to acute sinusitis were selected for this review.

RESULTS

All patients were male with rapid onset of periorbital signs, absence of purulent rhinorrhea, and presence of significant thrombocytosis (exceeding 500 × 10(9)/L). The 38-day-old newborn had mixed infection of methicillin-resistant coagulase-negative Staphylococcus bacteremia and local Acinetobacter eye infection with Staphylococcus aureus in the SPOA. All had medially located SPOA that was adequately drained via endoscopic sinus surgery, resulting in full recovery.

CONCLUSION

Newborns with preexisting risk factors and immature immunity are at risk of severe and rare infections. Contrast-enhanced paranasal sinus computed tomographic scan is mandatory and reliable to differentiate preseptal and postseptal orbital infection, as both conditions can present similarly and rapidly deteriorate. In the contrast-enhanced computed tomography-demonstrable SPOA, endoscopic sinus surgery drainage of the abscess proved to be safe and reliable as the main treatment modality. All patients recovered well without complications.

Two cases of necrotizing fasciitis due to Acinetobacter baumannii

Necrotizing fasciitis has conventionally been associated with the streptococci, and when it is caused by other organisms, it is most often the result of a polymicrobial infection. We report on two cases of fatal monomicrobial necrotizing fasciitis due to Acinetobacter baumannii, an unusual finding that may be an indication of enhanced virulence of the organism.

Chlamydial conjunctivitis presenting as pre septal cellulitis

Chlamydia conjuctivitis results from infection by chlamydia trachomatis, the commonest treatable sexually transmitted infection in Europe. Its clinical manifestations involve the conjunctiva and the cornea. The inflammation under the upper eyelid may be sufficient to present as ptosis, however previously it has not been documented to cause a preseptal cellulitis. We present such a case.

A 15-year-old girl was diagnosed with a left viral conjunctivitis. Five days later, she returned with marked oedema of the left upper and lower lids accompanied by erythema. The tarsal conjunctiva revealed follicles and large papillae and extra ocular movements revealed discomfort on elevation. A secondary diagnosis of bacterial pre septal cellulitis was made and the treatment was changed a broad spectrum oral antibiotic. On review at two days, the patient now complained of a large amount of purulent discharge in association with the marked pre septal swelling. As previous bacteriology and virology had been negative, the patient was re swabbed for chlamydia. This proved positive and her symptoms completely resolved following administration of Azithromycin.

In this particular case recognition of the pathogen is important to alert the patient to the likelihood of unknown genital infestation. In all cases of positive culture, the patient should be counselled to attend a genitourinary clinic and to alert any sexual partners to the need to do likewise.