Cyst infections in patients with autosomal dominant polycystic kidney disease

BACKGROUND AND OBJECTIVES

Cyst infection is a complex diagnostic and therapeutic issue in patients with autosomal dominant polycystic kidney disease (ADPKD); however, published data regarding the diagnosis and the management of cyst infections in patients with ADPKD are sparse.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A retrospective study was conducted in a referral center for patients with ADPKD in Paris, France. We identified using a computerized database all patients who had ADPKD and were admitted in the nephrology department of Hôpital Necker between January 1998 and August 2008 with likely or definite renal and/or hepatic cyst infection. Medical files of all included patients were reviewed.

RESULTS

Among 389 identified patients with ADPKD, 33 (8.4%) had 41 episodes of cyst infection, including eight definite and 33 likely cases. The incidence of cyst infections in patients with ADPKD was 0.01 episode per patient per year. Microbiological documentation was available for 31 episodes (75%), Escherichia coli accounting for 74% of all retrieved bacterial strains. Positron emission tomography scan proved superior to ultrasound, Computed tomography scan, and magnetic resonance imaging for the detection of infected cysts. Clinical efficacy of initial antibiotic treatment was noted in 71% of episodes. Antibiotic treatment modification was more frequently required for patients who were receiving initial monotherapy compared with those who were receiving bitherapy. Large (diameter >5 cm) infected cysts frequently required drainage.

CONCLUSIONS

Positron emission tomography scan will probably make the diagnosis of cyst infections easier and more accurate. Antibiotic association, including a fluoroquinolone, and the drainage of large infected cysts remain the main treatment for cyst infections.

Pathogenic Variants in Complement Genes and Risk of Atypical Hemolytic Uremic Syndrome Relapse after Eculizumab Discontinuation

BACKGROUND AND OBJECTIVES

The complement inhibitor eculizumab has dramatically improved the outcome of atypical hemolytic uremic syndrome. However, the optimal duration of eculizumab treatment in atypical hemolytic uremic syndrome remains debated. We report on the French atypical hemolytic uremic syndrome working group's first 2-year experience with eculizumab discontinuation in patients with atypical hemolytic uremic syndrome.

DESIGN, SETTING, PARTICIPANTS & MEASUREMENTS

Using the French atypical hemolytic uremic syndrome registry database, we retrospectively identified all dialysis-free patients with atypical hemolytic uremic syndrome who discontinued eculizumab between 2010 and 2014 and reviewed their relevant clinical and biologic data. The decision to discontinue eculizumab was made by the clinician in charge of the patient. All patients were closely monitored by regular urine dipsticks and blood tests. Eculizumab was rapidly (24-48 hours) restarted in case of relapse.

RESULTS

Among 108 patients treated with eculizumab, 38 patients (nine children and 29 adults) discontinued eculizumab (median treatment duration of 17.5 months). Twenty-one patients (55%) carried novel or rare complement genes variants. Renal recovery under eculizumab was equally good in patients with and those without complement gene variants detected. After a median follow-up of 22 months, 12 patients (31%) experienced atypical hemolytic uremic syndrome relapse. Eight of 11 patients (72%) with complement factor H variants, four of eight patients (50%) with membrane cofactor protein variants, and zero of 16 patients with no rare variant detected relapsed. In relapsing patients, early reintroduction (≤48 hours) of eculizumab led to rapid (<7 days) hematologic remission and a return of serum creatinine to baseline level in a median time of 26 days. At last follow-up, renal function remained unchanged in nonrelapsing and relapsing patients compared with baseline values before eculizumab discontinuation.

CONCLUSIONS

Pathogenic variants in complement genes were associated with higher risk of atypical hemolytic uremic syndrome relapse after eculizumab discontinuation. Prospective studies are needed to identify biomarkers predictive of relapse and determine the best strategy of retreatment in relapsing patients.

Shiga Toxin-Associated Hemolytic Uremic Syndrome: A Narrative Review

The severity of human infection by one of the many Shiga toxin-producing Escherichia coli (STEC) is determined by a number of factors: the bacterial genome, the capacity of human societies to prevent foodborne epidemics, the medical condition of infected patients (in particular their hydration status, often compromised by severe diarrhea), and by our capacity to devise new therapeutic approaches, most specifically to combat the bacterial virulence factors, as opposed to our current strategies that essentially aim to palliate organ deficiencies. The last major outbreak in 2011 in Germany, which killed more than 50 people in Europe, was evidence that an effective treatment was still lacking. Herein, we review the current knowledge of STEC virulence, how societies organize the prevention of human disease, and how physicians treat (and, hopefully, will treat) its potentially fatal complications. In particular, we focus on STEC-induced hemolytic and uremic syndrome (HUS), where the intrusion of toxins inside endothelial cells results in massive cell death, activation of the coagulation within capillaries, and eventually organ failure.

Use of High-Flow Nasal Cannula Oxygen Therapy in Subjects With ARDS: A 1-Year Observational Study

BACKGROUND

Beneficial effects of high-flow nasal cannula (HFNC) oxygen on oxygenation and respiratory parameters have been reported in a small number of subjects with acute respiratory failure (ARF). We aimed to evaluate its effect in subjects with ARDS.

METHODS

This was an observational single-center study. Prospectively obtained data were retrospectively analyzed. All patients admitted over 1 y to a university hospital medicosurgical ICU were included. Classification was according to the highest ventilatory support required. HFNC indications were reviewed, and demographics, clinical characteristics, and course of subjects with ARDS according to intubation need were compared.

RESULTS

Of 607 subjects admitted, 560 required ventilatory or oxygen support, among whom 180 received noninvasive ventilatory support. HFNC was used in 87 subjects and as first-line treatment in 51 subjects (29% of first-line noninvasively treated subjects), 45 of which had ARDS (PaO2 /FIO2 of 137 mm Hg; 22 men, 57.9 y of age). Pneumonia accounted for 82% of ARDS causes. The intubation rate in these subjects was 40%. Higher Simplified Acute Physiology Score II (SAPS II; 46 vs 29, P=.001), occurrence of additional organ failure (76% vs 26%, P=.002), mainly hemodynamic (50% vs 7%, P=.001) or neurological (22% vs 0, P=.01), and trends toward lower PaO2 /FIO2 and higher breathing frequency after HFNC initiation were evidenced in subjects who failed HFNC. Higher SAPS II scores were associated with HFNC failure in multivariate analysis.

CONCLUSIONS

In daily care, over one fourth of subjects requiring noninvasive ventilatory support were treated via HFNC, with a high success rate in subjects with severe ARDS. We conclude that HFNC may be considered as first-line therapy in ARF, including patients with ARDS.

Incidence, risk factors and clinical consequences of neutropenia following kidney transplantation: a retrospective study

Neutropenic episodes in kidney transplant patients are poorly characterized. In this retrospective study, neutropenia was experienced by 112/395 patients (28%) during the first year posttransplant. The only factor found to be significantly associated with the occurrence of neutropenia was combined tacrolimus-mycophenolate therapy (p < 0.001). Neutropenic patients experienced more bacterial infections (43% vs. 32%, p = 0.04). Grade of neutropenia correlated with the global risk of infection. Discontinuation of mycophenolic acid (MPA) due to neutropenia was associated with an increased incidence of acute rejection (odds ratios per day 1.11, 95% confidence intervals 1.02-1.22) but not with reduced renal function at 1 year. The time from onset of neutropenia to MPA discontinuation correlated with the duration of neutropenia. Granulocyte colony-stimulating factor (G-CSF) administration was safe and effective in severely neutropenic kidney graft recipients, with absolute neutrophil count >1000/microL achieved in a mean of 1.5+/-0.5 days. Neutropenia is an important and frequent laboratory finding that may exert a significant influence on outcomes in kidney transplantation. As well as leading to an increased incidence of infection, it is associated with a higher rate of allograft rejection if MPA is discontinued for >6 days (p = 0.02). G-CSF accelerates recovery of neutropenia and may be a good therapeutic alternative for severely neutropenic patients.

Invariant natural killer T cells and TGF-beta attenuate anti-GBM glomerulonephritis

Invariant natural killer T (iNKT) cells represent a particular subset of T lymphocytes capable of producing several cytokines, which exert regulatory or effector functions, following stimulation of the T cell receptor. In this study, we investigated the influence of iNKT cells on the development of experimental anti-glomerular basement membrane glomerulonephritis (anti-GBM GN). After injection of anti-GBM serum, the number of kidney iNKT cells rapidly increased. iNKT cell-deficient mice (Jalpha18-/-) injected with anti-GBM serum demonstrated worse renal function, increased proteinuria, and greater glomerular and tubular injury compared with similarly treated wild-type mice. We did not detect significant differences in Th1/Th2 polarization in renal tissue that might have explained the severity of disease in Jalpha18-/- mice. Interestingly, expression of both TGF-beta and TGF-beta-induced (TGFBI) mRNA was higher in wild-type kidneys compared with Jalpha18-/- kidneys, suggesting a possible protective role for TGF-beta in anti-GBM GN. Administration of an anti-TGF-beta neutralizing antibody significantly enhanced the severity of disease in wild-type, but not Jalpha18-/-, mice. In conclusion, in experimental anti-GBM GN, iNKT cells attenuate disease severity and TGF-beta has a renoprotective role.

Use of desmopressin acetate in severe hyponatremia in the intensive care unit

BACKGROUND AND OBJECTIVES

Excessive correction of chronic and profound hyponatremia may result in central pontine myelinolysis and cause permanent brain damage. In the case of foreseeable or established hyponatremia overcorrection, slowing down the correction rate of sodium plasma levels (PNa) or reinducing mild hyponatremia may prevent this neurologic complication.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This retrospective and observational study was performed with 20 consecutive patients admitted to two intensive care units for severe hyponatremia, defined by PNa <120 mmol/L and/or neurologic complications ascribable to hyponatremia and subsequently treated by desmopressin acetate (DDAVP) during correction of hyponatremia when the rate of correction was overtly or predictably excessive. The primary endpoint was the effectiveness of DDAVP on PNa control.

RESULTS

DDAVP dramatically decreased the rate of PNa correction (median 0.81 mmol/L per hour [interquartile range, 0.46, 1.48] versus -0.02 mmol/L per hour [-0.16, 0.22] before and after DDAVP, respectively; P<0.001) along with a concurrent decrease in urine output (650 ml/h [214, 1200] versus 93.5 ml/h [43, 143]; P=0.003), and a rise in urine osmolarity (86 mmol/L [66, 180] versus 209 mmol/L [149, 318]; P=0.002). The maximal magnitude of PNa variations was also markedly reduced after DDAVP administration (11.5 mmol/L [8.25, 14.5] versus 5 mmol/L [4, 6.75]; P<0.001). No patient developed seizures after DDAVP or after subsequent relowering of PNa that occurred in 11 patients.

CONCLUSIONS

Desmopressin acetate is effective in curbing the rise of PNa in patients admitted in the intensive care unit for severe hyponatremia, when the initial rate of correction is excessive.

Hypervirulent Klebsiella pneumoniae, a 5-year study in a French ICU

PURPOSE

Hypervirulent Klebsiella pneumoniae (hvKp) has emerged as a leading cause of severe community-acquired pneumonia, liver abscess and disseminated infection in the Far East. Data regarding the incidence, clinical features and microbiological characteristics related to hvKp infections in the Western world are scarce.

METHODOLOGY

The incidence, clinical features and microbiological characteristics of hvKp infections were investigated through a 5-year survey conducted in a single French intensive care unit. K. pneumoniae strains were screened for hypermucoviscosity based on a string test. Multilocus sequence typing and multiplex PCR analysis targeting virulence genes were performed on string test-positive strains.

RESULTS

Over a 53-month period, a total of 59 infections due to K. pneumoniae were identified including 26 community-onset infections. Twelve hvKp infections were documented, accounting for 46.1 % of community-acquired K. pneumoniae. Community-acquired pneumonia (n=6), aspiration pneumonia (n=4) and liver abscess (n=2) represented initial sites and mode of infection. Compared to non-hvKp infections, patients with hvKp infections displayed higher rates of multi-organ failure (83.3 % vs 35.7 %; P=0.04), but mortality rates were not different (50 % vs 35 %; P=0.71). Strains K1/ST23 (n=5) and K2/ST86 (n=5) predominated. All hvKp strains displayed wild-type susceptibility.

CONCLUSION

hvKp represent a potentially underestimated cause of fatal infections in the Western world.

Acute kidney injury in critical care: experience of a conservative strategy

PURPOSE

Renal replacement therapy (RRT) is a major supportive treatment of acute kidney injury (AKI) in intensive care unit (ICU), but the timing of its initiation remains open to debate.

MATERIALS AND METHODS

We retrospectively analyzed ICU patients who had AKI associated with at least one usual RRT criteria: serum creatinine concentration greater than 300 μmol/L, serum urea concentration greater than 25 mmol/L, serum potassium concentration greater than 6.5 mmol/L, severe metabolic acidosis (arterial blood pH<7.2), oliguria (urine output<135 mL/8 hours or <400 mL/24 hours), overload pulmonary edema. To estimate the risk of death associated with RRT adjusted for risk factors, we performed a marginal structural Cox model with inverse-probability-of-treatment-weighted estimator.

RESULTS

Among 4173 patients admitted to the ICU, 203 patients fulfilled potential RRT criteria. Ninety-one patients (44.8%) received RRT and 112 (55.2%) did not. Non-RRT and RRT patients differed in terms of severity of illness: Simplified Acute Physiology Score II (55±17 vs 60±19, respectively; P<.05) and Sequential Organ Failure Assessment score (8 [5-10] vs 9 [7-11], respectively; P=.01). Crude analysis indicated a lower ICU mortality for non-RRT compared with RRT patients (18% vs 45%; P<.001). In the marginal structural Cox model, RRT was associated with increased mortality (P<.01).

CONCLUSION

A conservative approach of AKI was not associated with increased mortality.

Severe Measles Infection: The Spectrum of Disease in 36 Critically Ill Adult Patients

France has recently witnessed a nationwide outbreak of measles. Data on severe forms of measles in adults are lacking. We sought to describe the epidemiologic, clinical, treatment, and prognostic aspects of the disease in adult patients who required admission to an intensive care unit (ICU). We performed a retrospective analysis of a cohort of 36 adults admitted to a total of 64 ICUs throughout France for complications of measles from January 1, 2009, to December 31, 2011. All cases of measles were confirmed by serologic testing and/or reverse transcription polymerase chain reaction.The cohort consisted of 21 male and 15 female patients, with a median age of 29.2 years (25th-75th interquartile range [IQR], 27.2-34.2 yr) and a median Simplified Acute Physiology Score (SAPS II) of 13 (IQR, 9-18). Among the 26 patients whose measles vaccination status was documented, none had received 2 injections. One patient had developed measles during childhood. Underlying comorbid conditions included chronic respiratory disease in 9 patients, immunosuppression in 7 patients, and obesity in 3 patients, while measles affected 5 pregnant women.Respiratory complications induced by measles infection led to ICU admission in 32 cases, and measles-related neurologic complications led to ICU admission in 2 cases. Two patients were admitted due to concurrent respiratory and neurologic complications.Bacterial superinfection of measles-related airway infection was suspected in 28 patients and was documented in 8. Four cases of community-acquired pneumonia, 6 cases of ventilator-associated pneumonia, 1 case of tracheobronchitis, and 2 cases of sinusitis were microbiologically substantiated.Of 11 patients who required mechanical ventilation, 9 developed acute respiratory distress syndrome (ARDS). Among the patients with ARDS, extraalveolar air leak complications occurred in 4 cases. Five patients died, all of whom were severely immunocompromised.On follow-up, 1 patient had severe chronic respiratory failure related to lung fibrosis, and 2 patients had mild lower limb paraparesis along with bladder dysfunction, both of which were ascribable to measles-induced encephalitis and myelitis. Among the 5 pregnant patients, the course of measles infection was uneventful, albeit 1 patient underwent emergent cesarean delivery because of fetal growth restriction.Measles is a disease with protean and potentially deceptive clinical manifestations, especially in the immunocompromised patient. Measles-associated pneumonitis and its complications, and less commonly postinfectious encephalomyelitis, are the main source of morbidity and mortality. In contrast with the usually benign course of the disease in immunocompetent patients, measles occurring in immunocompromised patients gives rise to lethal complications including ARDS, with or without bacterial superinfection. Other patients potentially at high risk for severe measles are young adults and pregnant women. Measles pneumonitis may predispose to air leak disease in patients using mechanical ventilation. To date, vaccination remains the most potent tool to control measles infection.

Endopeptidase Cleavage of Anti-Glomerular Basement Membrane Antibodies in vivo in Severe Kidney Disease: An Open-Label Phase 2a Study

BACKGROUND

The prognosis for kidney survival is poor in patients presenting with circulating anti-glomerular basement membrane (GBM) antibodies and severe kidney injury. It is unknown if treatment with an endopeptidase that cleaves circulating and kidney bound IgG can alter the prognosis.

METHODS

An investigator-driven phase 2a one-arm study (EudraCT 2016-004082-39) was performed in 17 hospitals in five European countries. A single dose of 0.25 mg/kg of imlifidase was given to 15 adults with circulating anti-GBM antibodies and an eGFR <15 ml/min per 1.73m². All patients received standard treatment with cyclophosphamide and corticosteroids, but plasma exchange only if autoantibodies rebounded. The primary outcomes were safety and dialysis independency at 6 months.

RESULTS

At inclusion, ten patients were dialysis dependent and the other five had eGFR levels between 7 and 14 ml/min per 1.73m². The median age was 61 years (range 19-77), six were women, and six were also positive for anti-neutrophil cytoplasmic antibodies. Then 6 hours after imlifidase infusion, all patients had anti-GBM antibodies levels below the reference range of a prespecified assay. At 6 months 67% (ten out of 15) were dialysis independent. This is significantly higher compared with 18% (nine out of 50) in a historical control cohort (P<0.001, Fisher's exact test). Eight serious adverse events (including one death) were reported, none assessed as probably or possibly related to the study drug.

CONCLUSIONS

In this pilot study, the use of imlifidase was associated with a better outcome compared with earlier publications, without major safety issues, but the findings need to be confirmed in a randomized controlled trial.Clinical Trial registration number: EUDRACT 2016-004082-39 https://www.clinicaltrialsregister.eu/ctr-search/trial/2007-001377-28/results.

Kidney Histopathology Can Predict Kidney Function in ANCA-Associated Vasculitides with Acute Kidney Injury Treated with Plasma Exchanges

BACKGROUND

Data from the PEXIVAS trial challenged the role of plasma exchange (PLEX) in ANCA-associated vasculitides (AAV). We aimed to describe kidney biopsy from patients with AAV treated with PLEX, evaluate whether histopathologic findings could predict kidney function, and identify which patients would most benefit from PLEX.

METHODS

We performed a multicenter, retrospective study on 188 patients with AAV and AKI treated with PLEX and 237 not treated with PLEX. The primary outcome was mortality or KRT at 12 months (M12).

RESULTS

No significant benefit of PLEX for the primary outcome was found. To identify patients benefitting from PLEX, we developed a model predicting the average treatment effect of PLEX for an individual depending on covariables. Using the prediction model, 223 patients had a better predicted outcome with PLEX than without PLEX, and 177 of them had >5% increased predicted probability with PLEX compared with without PLEX of being alive and free from KRT at M12, which defined the PLEX-recommended group. Risk difference for death or KRT at M12 was significantly lower with PLEX in the PLEX-recommended group (-15.9%; 95% CI, -29.4 to -2.5) compared with the PLEX not recommended group (-4.8%; 95% CI, 14.9 to 5.3). Microscopic polyangiitis, MPO-ANCA, higher serum creatinine, crescentic and sclerotic classes, and higher Brix score were more frequent in the PLEX-recommended group. An easy to use score identified patients who would benefit from PLEX. The average treatment effect of PLEX for those with recommended treatment corresponded to an absolute risk reduction for death or KRT at M12 of 24.6%.

CONCLUSIONS

PLEX was not associated with a better primary outcome in the whole study population, but we identified a subset of patients who could benefit from PLEX. However, these findings must be validated before utilized in clinical decision making.

Renal involvement in eosinophilic granulomatosis with polyangiitis (EGPA): a multicentric retrospective study of 63 biopsy-proven cases

OBJECTIVE

Eosinophilic granulomatosis with polyangiitis (EGPA) is a systemic small-vessel vasculitis characterized by asthma, hypereosinophilia and ANCA positivity in 40% of patients. Renal involvement is rare and poorly described, leading to this renal biopsy-proven based study in a large EGPA cohort.

METHODS

We conducted a retrospective multicentre study including patients fulfilling the 1990 ACR criteria and/or the 2012 revised Chapel Hill Consensus Conference criteria for EGPA and/or the modified criteria of the MIRRA trial, with biopsy-proven nephropathy.

RESULTS

Sixty-three patients [27 women, median age 60 years (18-83)] were included. Renal disease was present at vasculitis diagnosis in 54 patients (86%). ANCA were positive in 53 cases (84%) with anti-MPO specificity in 44 (83%). All patients had late-onset asthma. Peripheral neuropathy was present in 29 cases (46%), alveolar haemorrhage in 10 (16%). The most common renal presentation was acute renal failure (75%). Renal biopsy revealed pauci-immune necrotizing GN in 49 cases (78%). Membranous nephropathy (10%) and membranoproliferative GN (3%) were mostly observed in ANCA-negative patients. Pure acute interstitial nephritis was found in six cases (10%); important interstitial inflammation was observed in 28 (44%). All patients received steroids with adjunctive immunosuppression in 54 cases (86%). After a median follow-up of 51 months (1-296), 58 patients (92%) were alive, nine (14%) were on chronic dialysis and two (3%) had undergone kidney transplantation.

CONCLUSION

Necrotizing pauci-immune GN is the most common renal presentation in ANCA-positive EGPA. ANCA-negative patients had frequent atypical renal presentation with other glomerulopathies such as membranous nephropathy. An important eosinophilic interstitial infiltration was observed in almost 50% of cases.

Hyponatremia in the intensive care unit: How to avoid a Zugzwang situation?

Hyponatremia is a common electrolyte derangement in the setting of the intensive care unit. Life-threatening neurological complications may arise not only in case of a severe (<120 mmol/L) and acute fall of plasma sodium levels, but may also stem from overly rapid correction of hyponatremia. Additionally, even mild hyponatremia carries a poor short-term and long-term prognosis across a wide range of conditions. Its multifaceted and intricate physiopathology may seem deterring at first glance, yet a careful multi-step diagnostic approach may easily unravel the underlying mechanisms and enable physicians to adopt the adequate measures at the patient’s bedside. Unless hyponatremia is associated with obvious extracellular fluid volume increase such as in heart failure or cirrhosis, hypertonic saline therapy is the cornerstone of the therapeutic of profound or severely symptomatic hyponatremia. When overcorrection of hyponatremia occurs, recent data indicate that re-lowering of plasma sodium levels through the infusion of hypotonic fluids and the cautious use of desmopressin acetate represent a reasonable strategy. New therapeutic options have recently emerged, foremost among these being vaptans, but their use in the setting of the intensive care unit remains to be clarified.

Post-partum acute kidney injury: sorting placental and non-placental thrombotic microangiopathies using the trajectory of biomarkers

BACKGROUND

Among the severe complications of preeclampsia (PE), acute kidney injury (AKI) is problematic if features of thrombotic microangiopathy (TMA) are present. Although a haemolysis enzyme liver low-platelets syndrome is considerably more frequent, it is vital to rule out a flare of atypical haemolytic and uraemic syndrome (aHUS). Our objective was to improve differential diagnosis procedures in post-partum AKI.

METHODS

A total of 105 cases of post-partum AKI, admitted to nine different regional French intensive care units from 2011 to 2015, were analysed. Analysis included initial and final diagnosis, renal features, haemostasis and TMA parameters, with particular focus on the dynamics of each component within the first days following delivery. A classification and regression tree (CART) was used to construct a diagnostic algorithm.

RESULTS

AKI was attributed to severe PE (n = 40), post-partum haemorrhage (n = 33, including 13 renal cortical necrosis) and 'primary' TMA (n = 14, including 10 aHUS and 4 thrombotic thrombocytopenic purpura). Congruence between initial and final diagnosis was low (63%). The dynamics of haemoglobin, haptoglobin and liver enzymes were poorly discriminant. In contrast, the dynamic pattern of platelets was statistically different between primary TMA-related AKI and other groups. CART analysis independently highlighted the usefulness of platelet trajectory in the diagnostic algorithm. Limitations of this study include that only the most severe cases were included in this retrospective study, and the circumstantial complexity is high.

CONCLUSION

Trajectory of platelet count between admission and Day 3 helps to guide therapeutic decisions in cases of TMA-associated post-partum AKI. Our study also strongly suggests that during the post-partum period, there may be a risk of transient, slowly recovering TMA in cases of severe endothelial injury in women without a genetic mutation known to induce aHUS.

Bartonella and Coxiella infections presenting as systemic vasculitis: case series and review of literature

OBJECTIVES

Coxiella and Bartonella sp. display particular tropism for endothelial or endocardial tissues and an abnormal host response to infections with induced autoimmunity. We aimed, through a case series combined with a comprehensive literature review, to outline characteristics of Coxiella and Bartonella infections presenting as systemic vasculitis.

METHODS

We retrospectively included cases of definite Coxiella and Bartonella infections presenting with vasculitis features and performed a comprehensive literature review.

RESULTS

Six cases of Bartonella infections were added to 18 cases from literature review. Causative pathogens were mainly B. henselae. Bartonella infection mimicked anti-neutrophil cytoplasmic antibodies (ANCA)-associated vasculitis in 83% with PR3-ANCA and presented as cryoglobulinemic vasculitis in 8%. Glomerulonephritis was present in 92%, and 88% had endocarditis. Complement fractions were low in 82% and rheumatoid factor positive in 85%. Kidney biopsies showed cell proliferation, mostly crescentic, with pauci-immune glomerulonephritis in 29%. Outcome was favorable, with the use of antibiotics alone in one third. Five cases of Coxiella infections were added to 16 from literature review. Sixteen had small-vessel vasculitides, mainly cryoglobulinemia vasculitis in 75%. One patient had polyarteritis nodosa-like vasculitis and four large-vessel vasculitis. Outcome was good except for one death. A highly sensitive next generation sequencing analysis on 3 Coxiella and 2 Bartonella-related vasculitides biopsies did not find any bacterial DNA.

CONCLUSION

Coxiella and Bartonella are both able to induce vasculitis but display distinct vasculitis features. Bartonella mimics PR3-ANCA-associated vasculitis in the setting of endocarditis, whereas Coxiella may induce vasculitis involving all vessel sizes.

Epidemiology, clinical features, and management of severe hypercalcemia in critically ill patients

BACKGROUND

Severe hypercalcemia (HCM) is a common reason for admission in intensive-care unit (ICU). This case series aims to describe the clinical and biological features, etiologies, treatments, and outcome associated with severe HCM. This study included all patients with a total calcemia above 12 mg/dL (3 mmol/L) admitted in two ICUs from January 2007 to February 2017.

RESULTS

131 patients with HCM were included. HCM was related to hematologic malignancy in 58 (44.3%), solid tumors in 29 (22.1%), endocrinopathies in 16 (12.2%), and other causes in 28 (21.3%) patients. 108 (82.4%) patients fulfilled acute kidney injury (AKI) criteria. Among them, 25 (19%) patients required renal replacement therapy (RRT). 51 (38.9%) patients presented with neurological symptoms, 73 (55.7%) patients had cardiovascular manifestations, and 50 (38.1%) patients had digestive manifestations. The use of bisphosphonates (HR, 0.42; 95% CI, 0.27-0.67; P < 0.001) was the only treatment significantly associated with a decrease of total calcemia below 12 mg/dL (3 mmol/L) at day 5. ICU and Hospital mortality rates were, respectively, 9.9% and 21.3%. Simplified Acute Physiologic Score (SAPS II) (OR, 1.05; 95% CI 1.01-1.1; P = 0.03) and an underlying solid tumor (OR, 13.83; 95% CI 2.24-141.25; P = 0.01) were two independent factors associated with hospital mortality in multivariate analysis.

CONCLUSIONS

HCM is associated with high mortality rates, mainly due to underlying malignancies. The course of HCM may be complicated by organ failures which are most of the time reversible with early ICU management. Early ICU admission and prompt HCM management are crucial, especially in patients with an underlying solid tumor presenting with neurological symptoms.

Shiga Toxin-Associated Hemolytic Uremic Syndrome: Specificities of Adult Patients and Implications for Critical Care Management

Shiga toxin-producing Escherichia coli-associated hemolytic uremic syndrome (STEC-HUS) is a form of thrombotic microangiopathy secondary to an infection by an enterohemorrhagic E. coli. Historically considered a pediatric disease, its presentation has been described as typical, with bloody diarrhea at the forefront. However, in adults, the clinical presentation is more diverse and makes the early diagnosis hazardous. In this review, we review the epidemiology, most important outbreaks, physiopathology, clinical presentation and prognosis of STEC-HUS, focusing on the differential features between pediatric and adult disease. We show that the clinical presentation of STEC-HUS in adults is far from typical and marked by the prevalence of neurological symptoms and a poorer prognosis. Of note, we highlight knowledge gaps and the need for studies dedicated to adult patients. The differences between pediatric and adult patients have implications for the treatment of this disease, which remains a public health threat and lack a specific treatment.

Multidisciplinary management of anti-PP1Pk or anti-P alloimmunization during pregnancy: A new case with anti-P and a literature review

BACKGROUND

Red blood cell alloimmunization is the first cause of fetal and neonatal anemia. Alloimmunizations with anti-PP1P^k or anti-P can cause recurrent miscarriages and hemolytic disease of the fetus and newborn in the 2nd and 3rd trimesters of pregnancy. We report on a pregnant patient immunized with anti-P and a history of recurrent miscarriages.

CASE REPORT

This P₂ ^k (GLOB:-1; P1PK:-1,3) patient had a first pregnancy marked by a caesarean at 38 weeks of gestation (WG) for non-reassuring fetal heart rate. Then, she had three early spontaneous miscarriages. The fifth pregnancy began with a high titer of anti-P at 128. Early initiation of treatment with Intravenous Immunoglobulins (IVIg) and plasma exchanges (PE) starting at 5 WG permitted us to reduce the titer of anti-P below 32. A healthy infant was delivered by caesarean at 38 WG without anemia at birth and no exchange transfusion was required.

DISCUSSION AND REVIEW OF THE LITERATURE

The P and P^k antigens are expressed on placental, trophoblastic, and embryonic cells. This explains why P₁ ^k (GLOB:-1; P1PK:1,3), P₂ ^k (GLOB:-1; P1PK:-1,3), or Tj(a-)/p (GLOB:-1; P1PK:-1,-3) patients are prone to recurrent abortions in the first trimester of pregnancy. A literature review demonstrated 87% (68/78) of miscarriages in p patients. However, publication biases are possible with the most severe cases being reported.

CONCLUSION

Immunizations to P and PP1P^k antigens differ from others in their physiopathology and precocity. The association of PE and IVIg seems to be an effective treatment in the management of anti-PP1P^k or anti-P fetomaternal incompatibilities.

Malaria, Collapsing Glomerulopathy, and Focal and Segmental Glomerulosclerosis

BACKGROUND AND OBJECTIVES

Malaria, a potentially life-threatening disease, is the most prevalent endemic infectious disease worldwide. In the modern era, the spectrum of glomerular involvement observed in patients after malarial infections remains poorly described.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We therefore performed a retrospective multicenter study to assess the clinical, biologic, pathologic, and therapeutic characteristics of patients with glomerular disease demonstrated by kidney biopsy in France within 3 months of an acute malaria episode.

RESULTS

We identified 23 patients (12 men), all but 1 of African ancestry and including 10 patients with concomitant HIV infection. All of the imported cases were in French citizens living in France who had recently traveled back to France from an endemic area and developed malaria after their return to France. Eleven patients had to be admitted to an intensive care unit at presentation. Plasmodium falciparum was detected in 22 patients, and Plasmodium malariae was detected in 1 patient. Kidney biopsy was performed after the successful treatment of malaria, a mean of 24 days after initial presentation. At this time, all patients displayed AKI, requiring KRT in 12 patients. Nephrotic syndrome was diagnosed in 17 patients. Pathologic findings included FSGS in 21 patients and minimal change nephrotic syndrome in 2 patients. Among patients with FSGS, 18 had collapsing glomerulopathy (including 9 patients with HIV-associated nephropathy). In four patients, immunohistochemistry with an antibody targeting P. falciparum histidine-rich protein-2 demonstrated the presence of the malaria antigen in tubular cells but not in podocytes or parietal epithelial cells. An analysis of the apoL1 risk genotype showed that high-risk variants were present in all seven patients tested. After a mean follow-up of 23 months, eight patients required KRT (kidney transplantation in two patients), and mean eGFR for the other patients was 51 ml/min per 1.73 m².

CONCLUSIONS

In patients of African ancestry, imported Plasmodium infection may be a new causal factor for secondary FSGS, particularly for collapsing glomerulopathy variants in an APOL1 high-risk variant background.