Severe hypocalcemia after denosumab administration in a patient with chronic kidney disease: a case report.

Patients with altered kidney function are at increased risk of hypocalcemia after denosumab administration. There is however a small number of studies and case reports describing hypocalcemia refractory to treatment. We describe a case of severe hypocalcemia, after the administration of three doses of denosumab, in a young patient with lupus nephritis under corticosteroid coverage and osteopenia. However, more studies are needed in order to extract a safe conclusion about the factors that contribute to the development of severe hypocalcemia in this group of patients.

Hypocomplementemia is associated with more severe renal disease and worse renal outcomes in patients with ANCA-associated vasculitis: a retrospective cohort study.

BACKGROUND: The complement system has been recently proposed to play an important role in the pathogenesis of ANCA-associated vasculitis (AAV). This study evaluated the value of serum and kidney deposited C3 in predicting renal outcomes in AAV. METHODS: This was a retrospective study of 47 patients with AAV, who were categorized according to their serum C3 levels as hypo- or normo-complementemic and to those with positive or negative kidney biopsy immunofluorescence (IF) for C3. Baseline characteristics as well as progression to end-stage renal disease (ESRD) between the 2 groups were compared. RESULTS: In total, 23% (11/47) were hypo-complementemic; these patients were older (74 vs. 65 years, p = 0.013), had higher creatinine levels (4.9 vs. 2.2 mg/dL, p = 0.006), were more often hemodialysis dependent (64% vs. 19%, p = 0.009) and progressed more often to ESRD (55% vs. 11%, p = 0.01) compared to normo-complementemic patients (n = 36). On multivariate analysis, serum creatinine at diagnosis (HR = 16.8, 95%CI: 1.354-208.62, p = 0.028) and low serum C3 (HR = 2.492; 95% CI: 1.537-11.567; p = 0.044) were independent predictors for ESRD. Among 25 patients with an available kidney biopsy, 56% had C3 deposition by IF and displayed more often a mixed histological pattern (72% vs. 27%, p = 0.033), low serum C3 levels (42% vs. 18%, p < 0.001) and serious infections during follow-up (57% vs. 18%, p = 0.047) compared to those with negative (n = 11) IF staining. CONCLUSION: Almost one of four patients with AAV has low C3 levels at diagnosis which is associated with more severe renal disease and worse renal outcomes (ESRD). This should be taken into account in therapeutic and monitoring strategies.

Two cases of typical HUS in adults treated with an anti-C5 monoclonal antibody: a new perspective?

Hemolytic uremic syndrome (HUS) is a rare clinical entity, especially in adults. In its typical form the causative factor that triggers the cascade of immunologic and inflammatory events is a Shiga toxin-producing pathogen, found in the patient's stool. Renal and neurologic involvement usually prevails and requires immediate care. Regarding this potentially life-threatening condition, little is known and the mainstay is supportive care. However, some interesting evidence has come up about the use of eculizumab, an anti-C5 monoclonal antibody, mainly in pediatric patients with typical HUS. Herein, we present two cases with typical HUS caused by two different strains of Escherichia coli (Shiga toxin-producing enterohemorrhagic and enteropathogenic) who were both treated effectively with anti-C5 monoclonal antibodies (eculizumab and ravulizumab).

Urine Nephrin and Podocalyxin Reflecting Podocyte Damage and Severity of Kidney Disease in Various Glomerular Diseases-A Cross-Sectional Study.

Background/Objectives: Glomerulopathy is a term used to describe a broad spectrum of renal diseases, characterized by dysfunction of glomerular filtration barrier, especially of podocytes. Several podocyte-associated proteins have been found and proved their usefulness as urine markers of podocyte dysfunction. Two of them are nephrin (NEP) and prodocalyxin (PDC). This study aims to evaluate the association of podocyte damage, as it is demonstrated via the concentrations of urinary proteins, with clinical and histological data from patients with several types of glomerulonephritis. Methods: We measured urine levels of two podocyte-specific markers, NEP and PDC (corrected for urine creatinine levels), in patients with a wide range of glomerulopathies. Serum and urine parameters as well as histological parameters from renal biopsy were recorded. Results: In total, data from 37 patients with glomerulonephritis and 5 healthy controls were analyzed. PDC and NEP concentrations correlated between them and with serum creatinine levels (p = 0.001 and p = 0.013 respectively), and with histological lesions associated with chronicity index of renal cortex, such as severe interstitial fibrosis, severe tubular atrophy and hyalinosis (for PDC/NEP, all p < 0.05). In addition, the PDC and NEP demonstrated statistically significant correlations with interstitial inflammation (p = 0.018/p = 0.028). Regarding electron microscopy evaluation, PDC levels were correlated with distinct characteristics, such as fibrils and global podocyte foot process fusion, whereas the NEP/CR ratio was uniquely significantly associated with podocyte fusion only in non-immune-complex-mediated glomerulonephritis (p = 0.02). Among the other clinical and histological parameters included in our study, a strong correlation between proteinuria >3 g/24 h and diffuse fusion of podocyte foot processes (p = 0.016) was identified. Conclusions: Podocalyxin and nephrin concentrations in urine are markers of podocyte dysfunction, and in our study, they were associated both with serum creatinine and histological chronicity indices.

Pulmonary-Renal Syndrome During COVID-19 Pandemic Revealed a Rare Case of Anti-GBM Disease.

Anti-GBM disease is a rare, life-threatening small vessel vasculitis caused by circulating anti-GBM antibodies resulting to rapidly progressive glomerulonephritis and/or pulmonary haemorrhage. The gold standard for the diagnosis is the renal biopsy with the pathognomonic finding of linear deposition of IgG along the glomerular capillaries. Early diagnosis and intervention are key determinants of the response to therapy and long-term prognosis of these patients. However, during COVID-19 pandemic recognizing a pulmonary-renal syndrome caused by autoimmune diseases has become challenging. Herein, we aimed to describe a rare case of anti-GBM disease with pulmonary haemorrhage and rapidly progressive glomerulonephritis in a young man in a tertiary referral hospital in Greece, while COVID-19 pandemic was at its peak. Although the patient presented high level of creatinine and crescents, the early diagnosis and start of treatment resulted to favourable renal prognosis.

The prognostic value of speckle tracking echocardiography in patients with end stage renal disease on dialysis.

BACKGROUND: Chronic kidney disease (CKD) is associated with a higher incidence of cardiovascular death especially as the disease progresses and patients are on long-term dialysis treatment. Left ventricular (LV) dysfunction and cardiac deformation measured by speckle tracking echocardiography seem to play an important prognostic role in several different specific populations. OBJECTIVE: Τhe prognostic value of strain analysis measurements, including the novel diastolic parameters such as left atrial (LA) strain, in patients with end-stage renal disease on dialysis (stage 5 CKD). METHODS: 67 patients (mean age 62.3 ± 11.8, 65.7% men) with stage 5 CKD (45 on hemodialysis and 22 on peritoneal dialysis) were enrolled in the study protocol. The mean duration of dialysis was 102.48 ± 84.98 months. Mean follow-up lasted seven years. RESULTS: Most of the study population had normal or mildly impaired systolic function with a mean LV ejection fraction of 49.17% (± 10.41) while 70% of patients had impaired LV global longitudinal strain, mean 14.35% (± 4.49). Regarding LA strain parameters the mean LA reservoir, LA conduit, and LA contractile reserve were 24.11% (± 12.61), 10.56% (± 5.88), and 13.60% (± 9.15) respectively. Thus 50% of the population had impaired LA strain. Logistic regression analysis showed that of the various echocardiographic parameters LV ejection fraction, LV global longitudinal strain, and the conduit phase of LA strain were significantly associated with total prognosis (p = 0.009, p = 0.007, p = 0.05). The conduit element of LA strain was the strongest predictor among them, when adjusted for age (OR = 0.77 p = 0.04). CONCLUSIONS: Left ventricular diastolic dysfunction is an important prognostic factor in patients with advanced CKD on long-term dialysis, without known CAD. The novel echocardiographic parameters such as LA strain could add valuable information to the overall cardiac evaluation of this specific population.

Distal renal tubular acidosis and nephrocalcinosis as initial manifestation of primary sjögren's syndrome.

There is a well-established association between primary Sjögren's syndrome and distal renal tubular acidosis (dRTA). dRTA is a relatively infrequent manifestation of primary Sjögren's syndrome which can present with life-threatening electrolyte abnormalities while, in some patients, it could be the first manifestation of the syndrome. We report the case of a 35-year-old woman who presented with unexplained episodes of generalized weakness, severe hypokalemia, nephrocalcinosis, and normal anion gap metabolic acidosis. Subsequent evaluation revealed primary Sjögren's syndrome as her underlying condition. The patient responded well to potassium supplementation, sodium bicarbonate, and oral prednisolone. After four years of follow-up, there were no other extraglandular manifestations, the renal function remained stable and the acidosis was partially improved without the need for oral bicarbonate. This case demonstrates that dRTA could be the initial manifestation of primary Sjögren's syndrome and highlights the necessity for increased vigilance for patients presenting with persistent hypokalemia or nephrocalcinosis so that an early diagnosis can be made allowing for better control and prevention of disease progression.

Serious infections in ANCA-associated vasculitides in the biologic era: real-life data from a multicenter cohort of 162 patients.

BACKGROUND: Serious infections (SI) are common in patients with ANCA-associated vasculitides (AAV) like granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA). Real-life data regarding their incidence and predisposing factors-after the introduction of B cell depleting agents-are limited while data quantifying the risk per treatment modality and year of the disease are missing. Here, we aim to describe in details the incidence and the risk factors for SI in a contemporary AAV cohort. METHODS: Multicenter, observational, retrospective study of AAV patients followed in three tertiary referral centers. RESULTS: We included 162 patients with GPA (63%) and MPA (37%), males 51.9%, mean age 60.9 years, ΑΝCA+ 86%, and generalized disease 80%. During follow-up (891.2 patient-years, mean 5.4 years), 67 SI were recorded in 50 patients at an incidence rate of 7.5 per 100 patient-years. The SI incidence rate was higher during induction with cyclophosphamide (CYC) compared to rituximab (RTX, 19.3 vs. 11.3 per 100 patient-years, respectively) while it was lower and comparable between RTX and other regimens (5.52 vs. 4.54 per 100 patient-years, respectively) in the maintenance phase. By multivariate analysis, plasmapheresis (PLEX) and/or dialysis was a strong predictor for an SI during the 1st year after diagnosis (OR = 3.16, 95% CI 1.001-9.96) and throughout the follow-up period (OR = 5.21, 95% CI 1.93-14.07). In contrast, a higher baseline BVAS (OR = 1.11, 95% CI 1.01-1.21) was associated with SI only during the 1st year. CONCLUSIONS: In this real-life study of patients with AAV, the SI incidence was higher during CYC compared to RTX induction while there was no difference between RTX and other agents used for maintenance therapy. Higher disease activity at baseline and need for PLEX and/or dialysis were independent factors associated with an SI.