Elizabethkingia anophelis infection in an infant: an unusual presentation

Abstract

A 7-month-old male infant presented with history of fever for 2 weeks, multiple ecchymotic patches over face, trunk and lower limbs, and one episode of seizure. The infant had shock, respiratory failure, severe anaemia, thrombocytopenia and temporoparietal haematoma on CT scan of the head. He was managed with supportive care and broad-spectrum empiric antibiotics. Two consecutive blood cultures grew Elizabethkingia anophelis, sensitive only to piperacillin–tazobactam. The infant responded to therapy and was discharged after 2 weeks of hospital stay. Repeated coagulation studies done to rule out an underlying bleeding disorder were negative. There was no clue in favour of non-accidental trauma. We report this case to highlight the unusual clinical presentation of this emerging pathogen. Mostly reported in outbreaks from surgical and post-operative intensive care units, it was worrisome to find this infant presenting with community-acquired E. anophelis infection.

Background

Elizabethkingia anophelis and E. meningoseptica are the two medically important Elizabethkingia species.¹ Most E. anophelis infections are reported from cardiothoracic and surgical intensive care units. We report the case of an infant with community-acquired E. anophelis infection with intracranial and multiple skin bleeds to highlight an unusual presentation of this emerging pathogen.

Case presentation

A 7-month-old male infant had fever for 2 weeks, accompanied by skin lesions over face and trunk followed by progressively enlarging bluish patches over both the thighs (figure 1). He had one episode of generalised seizure and altered sensorium 1 day prior to admission. He was managed at a local hospital for 12 hours with antiepileptics, antibiotics and blood transfusion in view of low haemoglobin (4 g/dL).

Figure 1.

Ecchymotic patches on bilateral lower limbs in an infant with Elizabethkingia anophelis sepsis.

On presentation to our hospital, the infant had shock and respiratory failure requiring mechanical ventilation. Shock was managed with fluid boluses and inotropes. The infant was malnourished with marked pallor and hepatomegaly. There was no focal neurological deficit. CT scan of head revealed left temporoparietal haemorrhage. Hemogram showed anaemia (Hb 6.9 g/dL), thrombocytopenia (platelet count 76 × 10⁹/L) and leucocyte count 12 000/mm³ (N68%, L24%, M8%). Other investigations: procalcitonin 1.12 ng/mL (0–0.07 ng/mL), C reactive protein 5.58 mg/L, urea 29 mg/dL, creatinine 0.2 mg/dL, alanine-transaminase 38 mg/dL, aspartate-transaminase 29 mg/dL, and bilirubin 4.7 mg/dL. Blood cultures sent at admission and on day 2 grew E. anophelis as detected by Matrix-assisted laser desorption ionization- time of flight (MALDI-TOF) mass spectrometry (VITEK-MS system, bioMérieux, Marcy-l’Étoile, France). E. anophelis was sensitive to piperacillin–tazobactam and resistant to other antibiotics tested (amikacin, cefotaxime, ceftazidime, cefoperazone-sulbactam, ciprofloxacin, imipenem and meropenem).

Differential diagnosis

Patient was evaluated for any underlying bleeding disorder. Peripheral smear was unremarkable. Prothrombin time and activated partial thromboplastin time repeated multiple times were normal. Clot solubility test and platelet-function assay were also normal. Antinuclear antibodies (ANA), anti-neutrophilic cytoplasmic antibody (ANCA) were negative and complement levels were normal (serum C3: 201 mg/dL; reference: 70–220 mg/dL). There were no social issues pointing to non-accidental injury. Other causes of fever with thrombocytopenia were ruled out with relevant investigations (negative dengue, leptospira and scrub typhus serology). In the absence of any other demonstrable cause of shock, thrombocytopenia, ecchymotic patches and intracerebral bleed, bacteraemia caused by E. anophelis was believed to be the inciting factor. There was no apparent source of infection or any contact with a medical personnel in the infant.

Treatment

Patient was initially started on meropenem and vancomycin. Shock resolved within 24 hours of paediatric intensive care unit (PICU) stay. After the culture/sensitivity reports, antibiotics were changed to piperacillin–tazobactam and vancomycin and child became afebrile within 48 hours of antibiotic change. Subsequent two blood cultures on day 7 and day 9 were sterile. Patient was extubated on day 6 and antibiotics were continued for 14 days.

Outcome and follow-up

The ecchymoses on thighs slowly resolved and the patient did not have any focal neurological deficit at discharge. On last follow-up at 6 months, he was doing well, gaining weight and did not have any bleeding episode.

Discussion

This case highlights an atypical presentation of E. anophelis infection with skin and intracranial bleeds, possibly acquired in a community-setting. We also want to highlight the use of MALDI-TOF mass spectrometry to identify and differentiate E. anophelis from another common species E. meningoseptica.

Elizabethkingia are non-motile, non-spore forming, aerobic gram-negative bacilli.¹ E. anophelis was discovered in 2011 from the midgut of Anopheles gambiae mosquito.² While Elizabethkingia species are widespread in nature, the environmental sources of E. anophelis infection are not clear. The first clinical case reported was an 8-day-old neonate with late-onset neonatal sepsis and meningitis with cerebrospinal fluid culture positive for Elizabethkingia species.³ E. anophelis was identified by 16s-rRNA sequencing. Teo et al reported an outbreak of E. anophelis in five patients admitted in cardiothoracic and surgical intensive care units.⁴ Outbreaks of E. anophelis infection have also been reported from Wisconsin (63 confirmed cases with mortality rate of 28%) and Illinois (at least 10 confirmed cases).⁵ Contaminated tap water and aerators have been implicated as sources of E. anophelis in hospital setting; however, potential sources of community-acquired infection are unclear.^6–8

Most E. anophelis infections occur in patients with underlying predisposition, like extremes of age, malignancy, immunosuppression, major surgery or critical illness.1 3 4 9 10 The most common clinical manifestations are pneumonia, catheter-related bloodstream infection and neonatal meningitis. The reported case fatality rate with E. anophelis infection ranges from 24% to 60%.¹

MALDI-TOF mass-spectrometry correctly identifies E. anophelis only if the database/library includes E. anophelis species, which is available in research settings.^{1 10} 16s-rRNA gene sequencing is a more accurate method for species identification.^{1 11} E. anophelis isolates are resistant to most beta-lactams, carbapenems and aminoglycosides.¹² In our case, E. anophelis was sensitive only to piperacillin–tazobactam. The cause of bleeding was unclear and was possibly caused by vascular injury triggered by E. anophelis sepsis along with thrombocytopenia.

Patient’s perspective.

We were very worried at the start as our baby had multiple bleedings and infection. However, after he was taken out of ventilator, we had some positive hope. We thank the team of doctors and nurses for supporting and saving our baby.

Learning points.

• Elizabethkingia anophelis is an emerging pathogen affecting patients of all age groups, in particular those with underlying predisposition.

• While mostly reported in the form of outbreaks from intensive care units, E. anophelis can also present in other settings including the possible community acquired infection. However, the environmental sources of E. anophelis infection remain unclear.

• The most common clinical manifestations are pneumonia, catheter-related bloodstream infection and neonatal meningitis. However, the presentation in our case was quite unusual in the form of bleeding.

• The antibiotic resistance pattern demonstrated by E. anophelis is worrisome.

Ethics statements

Patient consent for publication

Obtained.