Moraxella lacunatainfection accompanied by acute glomerulonephritis

Abstract

Moraxella lacunata (M. lacunata) is a Gram-negative bacterium, which rarely causes serious infection. This is a rare case report of acute glomerulonephritis diagnosed by pathological findings in a child accompanied by M. lacunata infection. The patient showed hematuria, proteinuria and hyperkalemia requiring emergency hemodialysis. After hospitalization, M. lacunata bacteremia became apparent. Pathological findings showed an increase in glomerulus inflammatory cells and glomerular C3 deposition was observed in the renal tissue biopsy. Final diagnosis was endocapillary proliferative glomerulonephritis. Clinical reports of M. lacunata infection requiring emergency hemodialysis in children are rare. Previous reports have suggested that lowered immune competency with chronic kidney disease may be a risk factor associated with serious invasive cases of M. lacunata infection. However, detailed clinical laboratory data and pathological findings have not been identified in previous case reports. Our case directly indicated complement activity and acute glomerulonephritis with M. lacunata infection. Although there are various causes for acute glomerulonephritis, infection-related glomerulonephritis (IRGN) is an important concept. M. lacunata infection might have a potential risk for IRGN with dysregulation of complement activity leading to serious and invasive clinical conditions than previously considered.

Eculizumab-Associated Moraxella lacunata Bacteremia and Systemic Inflammatory Response Syndrome in a Toddler with Atypical Hemolytic Uremic Syndrome

“…Of 5 children previously reported with invasive Moraxella lacunata infections, 4 had bacteremia and in 1 the organism was recovered from a patellar osteolytic lesion. [3][4][5][6]15 Of the 4 children with bacteremia, 2 had cardiac anomalies and developed infective endocarditis, 1 was previously well but developed meningitis, and the fourth was healthy but developed acute glomerulonephritis (Table 1). One child with infective endocarditis developed aortic valve vegetation while the other had mitral valve insufficiency.…”

“…It thus blocks the terminal complement cascade, without affecting the generation of C3b which is needed for opsonophagocytosis and shaping adaptive immune responses. 6,7 C5a is needed for upregulation of phagocytosis. 17 C5b binds to damaged or foreign surfaces which leads to the joining of C5b to C6-C9, thereby forming the membrane attack complex whose function is to form transmembrane channels that disrupt the cell membranes of target cells leading to their lysis and death.…”

“…17,18 Moraxella lacunata bacteremia, independent of eculizumab use, was noted to be associated with transient decreased concentrations of C3 and CH50 in a previously healthy 12-year-old boy with acute glomerulonephritis. 6…”

“…1,2 Rarely has this organism been identified as the cause of more serious illnesses, with only 4 prior case reports of bacteremic Moraxella lacunata infections in children (Table 1), none involving the use of immune-modulating agents as a predisposing risk factor. 3-6…”

“…1,2 Rarely has this organism been identified as the cause of more serious illnesses, with only 4 prior case reports of bacteremic Moraxella lacunata infections in children (Table 1), none involving the use of immune-modulating agents as a predisposing risk factor. [3][4][5][6] Atypical hemolytic uremic syndrome (aHUS) is characterized by dysregulation of the alternative complement pathway with excess production of the terminal complement complex C5b-9, leading to endothelial cell injury and thrombotic microangiopathy. 7 Eculizumab, a humanized chimeric anti-C5 monoclonal IgG-kappa immunoglobulin with a hybrid IgG 2 and IgG 4 Fc component, significantly reduces complement activation.…”