Moraxella lacunata Septic Arthritis in a Patient with Lupus Nephritis

Abstract

Moraxella lacunata is a rare, usually commensal gram-negative rod most commonly associated with eye infections. We report a unique case of noniatrogenic M. lacunata bacteremia and septic knee arthritis in a patient with class III-IV lupus nephritis and speculate on the association between invasive Moraxella infection and renal impairment. CASE REPORTOn 5 December 2008, a 24-year-old woman with lupus nephritis presented at her routine nephrology appointment with a 1-week history of increasing edema, arthralgia, and intermittent fevers. One week prior, she had been discharged from a referring institution on a prednisone taper for an acute lupus flare. She was taking 60 mg of prednisone per day with 500 mg of mycophenolate mofetil (CellCept; self-initiated) twice per day at the time of her nephrology appointment. Examination revealed severe lower-extremity pitting edema, swollen knees, and a tender, swollen right wrist. Movement of her left knee induced severe pain.At baseline, the patient's biopsy-proven class III-IV lupus nephritis was associated with mild joint swelling and minimal periorbital edema, typically responsive to corticosteroids and immunosuppressive therapy. Given her recent history of highdose steroid and immunosuppressant usage, investigation into a source of her worsening renal dysfunction separate from her underlying lupus nephritis was warranted.Laboratory studies indicated leukocytosis (white blood cell count, 24 ϫ 10 3 /l [normal range, 3.6 ϫ 10 3 to 11.0 ϫ 10 3 /l]) and acute renal failure requiring emergent hemodialysis (potassium level, 6.8 meq/liter [normal range, 3.5 to 5.1 meq/liter]; blood urea nitrogen level, 200 mg/dl [normal range, 7 to 25 mg/dl]; and creatinine level, 4.2 mg/dl [normal range, 0.7 to 1.6 mg/dl]). Fecal cultures were unrevealing, urine cultures revealed 50,000 to 100,00 CFU/ml of Citrobacter koseri, and two of two blood cultures grew Moraxella lacunata (Table 1). She remained febrile with persistent M. lacunata growth in two of two blood cultures on the second day of admission, despite therapy every 6 h with 2.25 g of intravenous piperacillin-tazobactam, chosen for its broad-spectrum coverage of gram-negative rods including pseudomonas. Further studies to evaluate the source of her persistent bacteremia were performed; an echocardiogram showed a small pericardial effusion with no evidence of endocarditis, and bilateral knee arthrocentesis revealed M. lacunata growth from left knee synovial fluid (Table 2).Following septic knee debridement, she clinically improved with 10 days of intravenous piperacillin-tazobactam and progressive advancement in her activities of daily living. She remained afebrile until discharge. Surveillance blood and synovial fluid cultures on the third day of admission revealed no further bacterial growth. She continued to improve with eventual resolution of her renal failure.This case highlights the invasive potential of M. lacunata and emphasizes the importance of searching for occult sources of infection, particularly in an immunocompromised ho...

Validating T-RFLP as a sensitive and high-throughput approach to assess bacterial diversity patterns in human anterior nares

“…It has also been suggested that independent of the immune status of the host, Moraxella spp. may be more invasive pathogens than previously thought (Piontek & Herrmann-Czylwik, 1993;Woodbury et al, 2009). While differences in colonization by S. aureus have been attributed to host factors such as host immunity, age, gender and/or environmental factors (García-Rodríguez & Fresnadillo Martínez, 2002), the data generated from these 100 anterior nares samples could not reveal any relationship between host factors and bacterial structure or colonization of a particular species.…”

“…It has also been suggested that independent of the immune status of the host, Moraxella spp. may be more invasive pathogens than previously thought (Piontek & Herrmann‐Czylwik, ; Woodbury et al ., ).…”

“…At this point, we have no evidence as to why this may be the case. Previous studies have shown the presence of organisms related to Moraxella lacunata and/or Moraxella nonliquefaciens in the anterior nares (Devi et al, 1991;Wos-Oxley et al, 2010), which usually are of low virulence and have most commonly been associated with eye infections, pneumonitis and pulmonary abscess, and occasionally upper respiratory tract infections (Rosett et al, 1976;Laukeland et al, 2002;Woodbury et al, 2009). Among the first reports, M. lacunata has been described in 11% of women suffering from epidemic follicular conjunctivitis (Ringvold et al, 1985).…”

Identification of <i>Moraxella lacunata</i> from pulmonary abscesses in three zoo herbivores

“…Moraxella bovis causes infectious bovine keratoconjunctivitis, known as pinkeye, in cattle and has been found in the nasal passages of cattle [6, 22]. Moraxella lacunata can cause conjunctivitis, keratitis, endocarditis, and otolaryngitis in humans [5, 9, 13, 23], but is rarely found in animal cases [7, 24].…”

“…In human, M. lacunata is normally found in the oral cavity, cranial respiratory tract, and conjunctiva [9, 11, 14]. It usually causes otitis, sinusitis, conjunctivitis, and pharyngitis in children and has been reported to cause keratitis, meningoencephalitis, skin and soft tissue infection, and systemic infections including endocarditis, septicemia, and septic arthritis in humans [3, 11, 13, 20, 23]. Furthermore, Moraxella spp.…”