Severe acute kidney injury in children owing to infective endocarditis-associated immune complex glomerulonephritis: a report of two cases

Diagnostic Abilities for Determining the Level of Blood Cryoglobulins in the Choice of Tactics for Operations on the Small Intestine

The study of the incidence of cryoglobulinemia is relevant in patients with an intestinal anastomotic leak. This study aims to determine a laboratory marker of the risk of small intestine anastomotic leak. The study was based on 96 patients who were subjected to resections of segments of the small intestine with the formation of intestinal anastomoses at the State Institution “Zaytsev V.T. Institute of General and Urgent Surgery of National Academy of Medical Sciences of Ukraine”. Of all the operated patients, there were 55.2% women and 44.8% men. Of the 96 patients examined, cryoglobulinemia was detected in the majority – 62.5% of patients, of which 4 were later proved to have inactive hepatitis C; the remaining 38.5% had no cryoglobulinemia. According to the existing theory of the autoimmune mechanism of postoperative surgical complications formation, the revealed decrease in the level of cryoglobulins on the second day could be related to their fixation in the microcirculatory bed and the development of immunocomplex inflammation. While the increase in the content of cryoglobulins in serum on the third day can be caused by their entry into the circulatory bed from deposition or fixation sites and the development of a secondary immune response. In patients with intestinal anastomosis failure after resection of intestinal segments, cryoglobulinemia rates increased more than 80 mg/l; this indicator could be used as a marker of postoperative complications.

Diagnostic and treatment challenge of unrecognized subacute bacterial endocarditis associated with ANCA-PR3 positive immunocomplex glomerulonephritis: a case report and literature review

BACKGROUND

Diagnosis and treatment of either ANCA disease or silent infection-related glomerulonephritis is complicated and is a huge treatment challenge when overlapping clinical manifestations occur. We report a case of ANCA-PR3 glomerulonephritis, nervous system involvement, hepatosplenomegaly and clinically silent subacute infectious endocarditis.

CASE PRESENTATION

A 57-year-old man with known mitral valve prolaps was admitted for unexplained renal failure with signs of nephritic syndrome, hepatosplenomegaly, sudden unilateral hearing loss, vertigo, malaise, new onset hemolytic anemia and thrombocytopenia. Immunoserology revealed positive c-anti-neutrophil cytoplasm antibody (ANCA)/anti-proteinase 3 (anti-PR3), mixed type crioglobulinemia and lowered complement fraction C3. Head MRI showed many microscopic hemorrhages. Common site of infection, as well as solid malignoma were ruled out. In accordance with clinical and laboratory findings, systemic vasculitis was assumed, although the etiology remained uncertain (ANCA-associated, cryoglobulinemic or related to unrecognized infection). After kidney biopsy, clinical signs of sepsis appeared. Blood cultures revealed Streptococcus cristatus. Echocardiography showed mitral valve endocarditis. Kidney biopsy revealed proliferative, necrotizing immunocomplex glomerulonephritis. Half a year later, following intravenous immunoglobulins, glucocorticoids, antibiotic therapy and surgical valve repair, the creatinine level decreased and c-ANCA and cryoglobulins disappeared. A second kidney biopsy revealed no residual kidney disease. Four years after treatment, the patient is stable with no symptoms or signs of vasculitis recurrence.

CONCLUSIONS

Here we describe the diagnostic and treatment challenge in a patient with unrecognized subacute bacterial endocarditis associated with ANCA-PR3 immunocomplex proliferative and crescentic glomerulonephritis. In patients with ANCA-PR3 immunocomplex glomerulonephritis and other overlapping manifestations suggesting systemic disease, it is important to recognize and aggressively treat any possible coexisting bacterial endocarditis, This is the most important step for a favorable patient outcome, including complete clinical and pathohistological resolution of the glomerulonephritis.

Infection-Related Glomerulonephritis

Acute postinfectious glomerulonephritis or infection-related glomerulonephritis has been associated with several viral or bacterial infections. Group A beta-hemolytic streptococcal infection is the prototypical cause of postinfectious glomerulonephritis and the main focus of this discussion. The clinical spectrum can vary widely, from asymptomatic microscopic hematuria incidentally detected on routine urinalysis to rapidly progressive glomerulonephritis with acute kidney injury requiring emergent dialysis. Other important causes include glomerulonephritis associated with endocarditis and ventriculoatrial shunt infections. Multiple renal pathologic conditions have been associated with hepatitis B and C infections.