Strategies to prevent SARS-CoV-2 transmission in hemodialysis centres across Europe - Lessons for the future

Background

Early reports on the pandemic nature of COVID-19 directed the nephrology community to develop infection prevention and control guidance. We aimed to make an inventory of strategies that dialysis centres followed to prevent infection with COVID-19 in the first pandemic wave.

Methods

We analyzed IPC measures taken by hemodialysis centres treating patients presenting with COVID-19 between March 1, 2020 and July 31, 2020 and that completed the European Renal Association COVID-19 Database centre questionnaire. Additionally, we made an inventory of guidelines published in European countries to prevent spread of SARS-CoV-2 in dialysis centres.

Results

Data from 73 dialysis units located in and bordering Europe were analyzed. All participating centres implemented IPC measures to mitigate the impact of SARS-CoV-2 during the first pandemic wave. Measures mentioned most often included triage with questions before entering the dialysis ward, measuring body temperature, hand disinfection, masking for all patients and staff, and personal protective equipment for staff members. These measures were also recommended in most of the 14 guidelines that were identified in the inventory of national guidelines and were also scored as being among the most important measures by the authors of this paper. Heterogeneity existed between centres and national guidelines regarding the minimal distance between dialysis chairs and recommendations regarding isolation and cohorting.

Conclusions

Although variation existed, measures to prevent transmission of SARS-CoV-2 were relatively similar across centres and national guidelines. Further research is needed to assess causal relationships between measures taken and spread of SARS-CoV-2.

MO208: De Novo Glomerulonephritides Following BNT162B2 COVID-19 Vaccine: A Case Series

BACKGROUND AND AIMS

The development and massive use of mRNA COVID-19 vaccine BNT162b2 has raised new concerns on triggering de novo immune-mediated diseases, in particular rare diseases as glomerulonephritis (GN), even if the security profile is excellent and severe reactions have been rare. In literature few similar cases were recently described [1, 2]. We report six cases of newly diagnosed GN after a two-dose regimen of SARS-CoV-2 vaccine, from a single tertiary care institution in Northern Italy.

METHOD

We described six cases of de novo GN occurring after massive use of Pfizer-BioNTech BNT162b2 COVID-19 vaccine from March 2021 to December 2021. All cases were biopsy proven. Baseline characteristics and laboratory findings, treatments and outcomes were based on review of medical records.

RESULTS

From April 2021, we observed two IgA nephropathies (IgA-N), one membranous nephropathy (MN), one membranoprolipherative GN (MPGN), one acute interstitial nephritis (aTIN) and one minimal change disease (MCD). Of note, one IgA-N presented with diffuse purpura as in IgA-vasculitis. The median age at vaccination was 52.8 years (min–max 18–67) and three (50%) were female; arterial hypertension was the most common comorbidity (50%). Only one subject contracted COVID-19 before vaccine (16.6%). None of the points showed any sign of renal disease before vaccine; at the time of disease onset, the median creatinine was 1.49 mg/dL (min–max 0.6–10.5 mg/dL) and proteinuria 3.0 g/24 h (min–max 0.9–13.8 g/24 h). All cases presented after the second dose (1 day to 6 months thereafter) and three (50%) were within 3 weeks from the vaccine. Of note, the aTIN developed after the vaccine during a long-time therapy with statins and relapsed after a rechallenge with a statin few months later. All the nephropathies were treated as per center practice, with an overall good response (four partial remissions and one complete remission). Given a target population of about 100 000–200 000 residents in our area, we could estimate an incidence rate of 4–8 cases/100 000 patient-years.

CONCLUSION

This small series has a lot of limitations including the small number of patients and we probably missed some cases in our area. Furthermore, we could not investigate a causal association, even if the timing of disease onset might be suspicious in three cases and the incidence seemed to be almost twice as the expected in Europe (about 2–4/100.000 patient-years). As for SARS-CoV-2 vaccines, it is likely that the mRNA vaccine will result in a more potent inflammatory stimulus than the one observed after inactivated virus-vaccine: maybe some patients had already a subclinical GN and the vaccine constituted a flare leading to the full-blown disease [3].

MO380INCREASED PREVALENCE OF ACUTE KIDNEY INJURY AND MORTALITY IN COVID-19 HOSPITALIZED PATIENTS

Background and Aims

In 2020, SARS-CoV-2 pandemic had a devastating impact on individuals and on national health systems worldwide. Although being primarily a lung disease, COVID-19-associated systemic inflammation and activation of coagulation/complement cascades lead to multiple organ dysfunction including Acute Kidney Injury (AKI).

Our aim is to evaluate AKI prevalence and mortality in hospitalized patients during COVID-19 pandemic in a 500-bed University Hospital.

Method

Observational study on 945 COVID-19 patients (March-May 2020). Data collection from Board Hospital Discharge and serum creatinine (Lab database). AKI stratification in accordance to KDIGO criteria and evaluation of outcome in the different subgroups. The same methodology was adopted to assess AKI prevalence and outcome in 2018-2019.

Results

351/945 (37.14%) of all hospital admissions for COVID-19 showed AKI further sub-classified as follows: 173 (18.3%) stage 1, 112 (11.9%) stage 2 and 66 (6.9%) stage 3: the control NO AKI group was 594/945 (62.86%). COVID-associated AKI prevalence was higher than that observed in 2018 (total AKI 17.9%, stage 1 10.7%, stage 2 4.5%, stage 3 2.7%) and 2019 (total AKI 17.2%, stage 1 10.1%, stage 2 4.5%, stage 3 2.6%).

During COVID-19 pandemic, in-hospital mortality was 27% for NO AKI group, 28% for total AKI group, further subdivided 24% for stage 1, 45% for stage 2 and 42% for stage 3 group, respectively. Mortality was different from that observed during 2018 (NO AKI 3.77%, total AKI 15.2%, stage 1 9.69%, stage 2 17.24%, stage 3 18.9%) and 2019 (NO AKI 3.56%, total AKI 18.35%, stage 1 10.6%, stage 2 20.1%, stage 3 24.3%).

In COVID-19 patients, mean age of NO AKI group was 64.6 ys vs. 71.7 ys of total AKI group divided in 71.6 ys for stage 1, 74.3 ys for stage 2 and 67.9 ys for stage 3, respectively. Mean eGFR at admission was 74.2 ml/min for NO AKI group, 61.3 ml/min for total AKI group divided in 64.3 ml/min for stage 1, 57.8 ml/min for stage 2 and 52.5 ml/min for stage 3. Mean serum creatinine at admission was 1.17 mg/dl in NO AKI group, 1.43 mg/dl for total AKI group divided in1.22 mg/dl for stage 1, 1.4 mg/dl for stage 2 and 2.25 mg/dl for stage 3.

Among evaluated comorbidities, only diabetes (p=0,048) and cognitive impairment (p=0,001) were associated with a significant increased risk for AKI development.

ICU admission rate was 5% for NO AKI group and 18% for total AKI group divided in 14% for stage 1, 22% for stage 2 and 44% for stage 3.

Mean length of hospital stay for NO AKI group was 7.22 days vs 15.08 days for total AKI group divided in 13.67 for stage 1, 15.83 for stage 2 and 21.82 for stage 3.

Of note, all different therapies administered to COVID-19 patients did not correlate with AKI incidence.

Mean eGFR at discharge was 76 ml/min for NO AKI group vs 66 ml/min for total AKI group divided in 68.7 ml/min for stage 1, 59.3 ml/min for stage 2 and 59.3 ml/min for stage 3. Mean serum creatinine at discharge was 1.14 mg/dl for NO AKI group vs 1.45 mg/dl for total AKI group divided in 1.28 mg/dl for stage 1, 1.58 mg/dl for stage 2 and 2.05 mg/dl for stage 3.

Conclusion

COVID-19 pandemic is associated with an increased AKI prevalence in hospitalized patients (2-fold increase in all KDIGO stages). AKI associated with an increased risk of mortality: of note, AKI stage2-3 had a strong impact on mortality in comparison to NO AKI group (OR 2.59 and 2.11, respectively). The presence of eGFR >60 ml/min and serum creatinine < 1.2 mg/dl at admission were associated with a lower risk of AKI development: reduced eGFR levels were observed at discharge particularly in AKI stage 2-3. The length of hospital stay and risk of ICU admission depended on AKI incidence and severity.

COVID-19 lead to an increased burden for Nephrologists due to increased AKI prevalence: a nephrological follow-up is needed to avoid progression from AKI to chronic kidney disease (CKD).

MO962EPIDEMIOLOGY AND CLINICAL RELEVANCE OF ACUTE KIDNEY INJURY IN KIDNEY TRANSPLANT RECIPIENTS

Background and Aims

Very few information about COVID-19 in kidney transplant recipients (KTRs) are known and the available evidence are based on limited case series. In KTRs, Acute Kidney Injury (AKI) of different causes is known to be associated with a decreased graft survival: direct viral infection and local inflammation may potentially lead to a premature loss of graft function and to an increased risk of death in COVID-19 patients.

To evaluate prevalence, stage, causes of AKI and mortality in KTRs with a positive pharyngeal swab for SARS-CoV-2 in our transplant center located in a 500-bed University Hospital.

Method

In March-June 2020, we evaluated in 25 COVID-19 KTRs demographic and transplant characteristics, comorbidities, immunosuppressive therapies (IT). Patients were screened for type of symptoms, management of IT, complications and outcome. AKI was graded according to 2012 KDIGO guidelines and causes were investigated basing on both clinical and laboratory variables. AKI prevalence in KTRs was compared to that observed in the whole hospitalized COVID-19 patients.

Results

During the first wave of pandemic, a total of 945 patients were admitted to our hospital with a reported AKI prevalence of 37%. AKI classified using 2012 KDIGO guidelines associated with an increased mortality risk in the whole population.

In this setting, we observed that 25 KTRs followed-up in our University Hospital had a positive molecular diagnosis for COVID-19: median age was 58 years and 80% were males. Considering the most frequent comorbidities, 100% of KTRs had hypertension and 7/25 (29%) had diabetes. Clinical symptoms at enrollment were fever (95%), cough (47%), dyspnea (30%). Regarding IT, 100% of patients were taking CNI, 64% antimetabolite agents and 76% steroids. Of note, 19/25 patients (76%) were hospitalized and 6/19 (31.5%) were admitted to Intensive Care Unit (ICU). Mean length of hospital stay was 23 days. At admission, all KTRs stopped MMF and increased steroid doses, concomitantly decreasing CNI levels.

AKI occurred in 60% of KTRs (12/25), AKI KDIGO grading as follow: stage 1 4/12 (33.3%), stage 2 3/12 (25%), stage 3 5/12 (41.7%); development favored by low eGFR/increased serum creatinine (mean serum creatinine 2.06 mg/dl): 4/25 (16%) required hemodialysis and the most frequent cause of AKI was sepsis or septic shock. Overall mortality in KTRs was 37,5% (9/25): of note, 88% (8/9) of patients with a worse outcome had developed AKI.

Conclusion

AKI prevalence was significantly higher in KTRs than in non-transplanted COVID-19 patients. AKI development was associated with an increased risk of mortality: of note, mortality rate in KTRs was significantly higher than that observed in the non-transplanted patients. COVID-19 lead to a difficult management of IT, in particular for elevated tacrolimus levels due to associated antiviral and antibiotic therapies. COVID-19-associated AKI in KTRs may lead to an increased risk of rejection and premature loss of graft function with the need of skilled nephrological follow-up.

Ultrasonographic Intraparenchymal Renal Resistive Index Variation for Assessing Renal Functional Reserve in Patients Scheduled for Cardiac Surgery: A Pilot Study

INTRODUCTION

Cardiac surgery-associated acute kidney injury (CSA-AKI) is a common complication in patients undergoing cardiac surgery. Preoperative renal functional reserve (RFR) has been demonstrated to be highly predictive of CSA-AKI. We have previously demonstrated that intraparenchymal renal resistive index variation (IRRIV) measured by ultrasound (US) can identify the presence of RFR in healthy individuals. This study aimed (1) to examine the correlation between the US IRRIV test and RFR measured through the protein loading test in patients undergoing elective cardiac surgery and (2) to determine the value of the 2 methods for predicting occurrence of AKI or subclinical AKI after cardiac surgery.

METHODS

Consecutive patients scheduled for cardiac surgery were enrolled for this pilot study. The protein loading test and the IRRIV test were performed in all patients 2 days before cardiac surgery. Correlation between IRRIV and RFR was tested using Pearson correlation analysis. Association between presence of RFR and positive IRRIV test, presence of RFR and AKI and subclinical AKI, and positive IRRIV test and AKI and subclinical AKI was evaluated using logistic regression analysis. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the values of IRRIV for predicting RFR, RFR for predicting AKI and subclinical AKI, and IRRIV for predicting AKI and subclinical AKI.

RESULTS

Among the 31 patients enrolled, significant association was found between IRRIV and RFR (r = 0.81; 95% CI: 0.63-0.90; p < 0.01). The association between RFR and IRRIV was described in 27/31 (87.1%) patients. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the IRRIV test were 100, 84, 60, and 100%, respectively. In ROC curve analysis, the area under the curve (AUC) was 0.80 (95% CI: 0.64-0.96). After cardiac surgery, 1/31 (3.2%) patient had AKI and 12/31 (38.7%) had subclinical AKI. RFR predicted subclinical AKI (odds ratio [OR] = 0.93; 95% CI: 0.87-0.98; p = 0.02). The sensitivity, specificity, PPV, and NPV of the RFR were 61, 88.8, 80, and 76%, respectively; the AUC was 0.75 (95% CI: 0.59-0.91). IRRIV predicts subclinical AKI (OR = 0.79; 95% CI: 0.67-0.93; p = 0.005). The sensitivity, specificity, PPV, and NPV of the IRRIV test were 46.1, 100, 100, and 72%, respectively; the AUC was 0.73 (95% CI: 0.58-0.87).

CONCLUSION

This pilot study suggests that a positive IRRIV test can significantly predict the presence of RFR in patients scheduled for cardiac surgery. RFR measured by the protein loading test or by the US IRRIV test can predict the occurrence of subclinical postoperative AKI. The findings of this study need to be confirmed in large patient cohorts.

A call to action to evaluate renal functional reserve in patients with COVID-19

Coronavirus disease 2019 (COVID-19) poses an unprecedented challenge to world health systems, substantially increasing hospitalization and mortality rates in all affected countries. Being primarily a respiratory disease, COVID-19 is mainly associated with pneumonia or minor upper respiratory tract symptoms; however, different organs can sustain considerable (if not terminal) damage because of coronavirus. Acute kidney injury is the most common complication of COVID-19-related pneumonia, and more than 20% of patients requiring ventilatory support develop renal failure. Additionally, chronic kidney disease is a major risk factor for COVID-19 severity and mortality. All these data demonstrate the relevance of renal function assessment in patients with COVID-19 and the need of early kidney-directed diagnostic and therapeutic approaches. However, the sole assessment of renal function could be not entirely indicative of kidney tissue status. In this viewpoint, we discuss the clinical significance and potential relevance of renal functional reserve evaluation in patients with COVID-19.

"War to the knife" against thromboinflammation to protect endothelial function of COVID-19 patients

In this viewpoint, we summarize the relevance of thromboinflammation in COVID-19 and discuss potential mechanisms of endothelial injury as a key point for the development of lung and distant organ dysfunction, with a focus on direct viral infection and cytokine-mediated injury. Entanglement between inflammation and coagulation and resistance to heparin provide a rationale to consider other therapeutic approaches in order to preserve endothelial function and limit microthrombosis, especially in severe forms. These strategies include nebulized heparin, N-acetylcysteine, plasma exchange and/or fresh frozen plasma, plasma derivatives to increase the level of endogenous anticoagulants (tissue factor pathway inhibitor, activated protein C, thrombomodulin, antithrombin), dipyridamole, complement blockers, different types of stem cells, and extracellular vesicles. An integrated therapy including these drugs has the potential to improve outcomes in COVID-19.

Subclinical Contrast-Induced Acute Kidney Injury in Patients Undergoing Cerebral Computed Tomography

INTRODUCTION

The nephrotoxicity of modern contrast media remains controversial. Novel biomarkers of kidney damage may help in identifying a subclinical structural renal injury not revealed by widely used markers of kidney function.

OBJECTIVE

The aim of this study was to investigate clinical (contrast-induced acute kidney injury [CI-AKI]) and subclinical CI-AKI (SCI-AKI) after intra-arterial administration of Iodixanol and Iopamidol in patients with an estimated glomerular filtration rate (eGFR) ≥60 mL/min/1.73 m2.

METHODS

This is a prospective observational monocentric study. Urinary sample was collected at 4-8 h after contrast medium exposure to measure neutrophil gelatinase associated lipocalin (NGAL) and the product tissue inhibitor of metalloproteinase-2 and insulin-like growth factor-binding protein 7 ([TIMP-2] × [IGFBP7]), while blood samples were collected at 24 and 48 h after exposure to measure serum creatinine.

RESULTS

One hundred patients were enrolled, of whom 53 were exposed to Iodixanol and 47 to Iopamidol. Patients in Iodixanol and Iopamidol groups were comparable in terms of demographics, pre-procedural and procedural data. No patient developed CI-AKI according KDIGO criteria, while 13 patients reported SCI-AKI after exposure to iodine-based medium contrast (3 patients in Iodixanol group and 10 patients in Iopamidol group), defined by positive results of NGAL and/or [TIMP-2] × [IGFBP7]. A positive correlation was found between NGAL and [TIMP-2] × [IGFBP7] in the analysed population (Spearman's rho 0.49, p < 0.001). In logistic regression analysis, Iopamidol exposure showed higher risk for SCI-AKI compared to Iodixanol (OR 4.5 [95% CI 1.16-17.52], p = 0.030), even after controlling for eGFR and volume of contrast medium used.

CONCLUSIONS

This study showed that intra-arterial modern contrast media administration may have a nephrotoxic effect in a population without pre-existing chronic kidney disease. Further investigations on larger scale are warranted to confirm if Iopamidol exposed patients to increased risk of SCI-AKI compared to Iodixanol.

Extracellular Vesicles as Mediators of Cellular Crosstalk Between Immune System and Kidney Graft

Extracellular vesicles (EVs) are known immune-modulators exerting a critical role in kidney transplantation (KT). EV bioactive cargo includes graft antigens, costimulatory/inhibitory molecules, cytokines, growth factors, and functional microRNAs (miRNAs) that may modulate expression of recipient cell genes. As paracrine factors, neutrophil- and macrophage-derived EVs exert immunosuppressive and immune-stimulating effects on dendritic cells, respectively. Dendritic cell-derived EVs mediate alloantigen spreading and modulate antigen presentation to T lymphocytes. At systemic level, EVs exert pleiotropic effects on complement and coagulation. Depending on their biogenesis, they can amplify complement activation or shed complement inhibitors and prevent cell lysis. Likewise, endothelial- and platelet-derived EVs can exert procoagulant/prothrombotic effects and also promote endothelial survival and angiogenesis after ischemic injury. Kidney endothelial- and tubular-derived EVs play a key role in ischemia-reperfusion injury (IRI) and during the healing process; additionally, they can trigger rejection by inducing both alloimmune and autoimmune responses. Endothelial EVs have procoagulant/pro-inflammatory effects and can release sequestered self-antigens, generating a tissue-specific autoimmunity. Renal tubule-derived EVs shuttle pro-fibrotic mediators (TGF-β and miR-21) to interstitial fibroblasts and modulate neutrophil and T-lymphocyte influx. These processes can lead to peritubular capillary rarefaction and interstitial fibrosis-tubular atrophy. Different EVs, including those from mesenchymal stromal cells (MSCs), have been employed as a therapeutic tool in experimental models of rejection and IRI. These particles protect tubular and endothelial cells (by inhibition of apoptosis and inflammation-fibrogenesis or by inducing autophagy) and stimulate tissue regeneration (by triggering angiogenesis, cell proliferation, and migration). Finally, urinary and serum EVs represent potential biomarkers for delayed graft function (DGF) and acute rejection. In conclusion, EVs sustain an intricate crosstalk between graft tissue and innate/adaptive immune systems. EVs play a major role in allorecognition, IRI, autoimmunity, and alloimmunity and are promising as biomarkers and therapeutic tools in KT.

[What if it is not an acute pyelonephritis? A monocentric experience of renal infarcts]

BACKGROUND

Often the reduced contrast enhancement on CT renal imaging is radiologically interpreted as acute pyelonephritis (PNA), but it is the task of the clinician to assess a possible differential diagnosis such as a renal infarct and look for a cause.

METHODS

In our experience (2010-2013), we hospitalized 51 patients with radiological imaging consistent with acute pyelonephritis in native kidneys. However, three of these cases result, after a second look, to be ischemic lesions, only sometimes complicated by over-infections (Tabella 1).

FIRST CASE

a woman hospitalized for fever and flank pain with blood culture positive for Klebsiella Pneumoniae. Antibiotic therapy allowed a clinical-laboratory improvement, but after 45 days persisted a focal wedge to the CT scan. The labs showed a anemia due to a sickle cell disease (SLC). The overview was finally interpreted as a renal infarct secondary to a sickle cell anemia, initially complicated by over-infection.

SECOND CASE

a men hospitalized for a acute flank pain. The CT scan showed a left renal infarct and a partial renal artery thrombosis, resulting in abuse of cannabinoids and LAC positivity.Third case: a woman hospitalized for flank pain and slight movement of inflammatory markers. CT showed a cuneiform area in the right kidney not vascularized, that did not resolved after prolonged antibiotic therapy. The labs evidence a heterozygous mutation of prothrombin and MTHFR causing the renal infarction.

CONCLUSIONS

6% of radiographic imaging consistent with acute pyelonephritis concealed an underlying infarct, due to a unknown state of thrombophilia. The presence of hypovascular imaging to the TC scan, therefore, requires a differential diagnosis between PNA and infarct, especially in the case of atypical development.

PEComa of soft tissues can mimic lymph node relapse in patients with history of testicular seminoma

Perivascular Epithelioid Cell tumour (PEComa) is rare. We describe a 39-year-old man who underwent a left radical orchidectomy and adjuvant radiation therapy for a stage IA classical testicular seminoma. He was diagnosed with a mass lateral to the right common iliac artery that was considered suspicious for late lymph node relapse after 3 years of follow-up. Due to the unusual location of the mass and the equivocal findings of percutaneous biopsy, a laparoscopic pelvic lymphadenectomy was performed. Final pathology revealed PEComa of soft tissue. The patient is disease-free after 38 months of follow-up without adjuvant treatment. The presence of rare soft-tissue neoplasm should be considered in differential diagnosis of retroperitoneal masses during follow-up of germ cell tumours. Suspicious isolated recurrences of these neoplasms in unusual locations can require surgical excision to confirm diagnosis and avoid inappropriate treatment.

Sex pheromone components of the European goat moth,Cossus cossus

Female tip washings of the European goat moth,Cossus cossus L., were found to contain the following compounds that are structurally similar to known pheromone components of Lepidoptera (%): decyl acetate (1.5), (Z)-5-dodecenol (1), (Z)-5-dodecenyl acetate (66), dodecyl acetate (12), (Z)-5-tetradecenyl acetate (14), tetradecyl acetate (4), and hexadecyl acetate (1.5). The washes contained an average of 125 ng of (Z)-5-dodecenyl acetate per female equivalent. EAG responses to nanogram amounts of the identified products indicated that (Z)-5-dodecenyl acetate was the most potent olfactory stimulant followed by (Z)-5-tetradecenyl acetate and (Z)-5-dodecenol, whereas the saturated acetates caused only weak depolarization. A strong EAG response was also recorded for (Z)-3-decenyl acetate, which was not detected in the female tip washings. Field results showed that (Z)-5-dodecenyl acetate was essential for the attraction of the males and that (Z)-3-decenyl acetate improved the attractiveness of (Z)-5-dodecenyl acetate alone or in combination with (Z)-5-tetradecenyl acetate.

[Optokinetic nystagmus and visual-vestibular interaction in subjects with "whiplash injuries"]

We studied the behaviour of Vestibular Nystagmus (VOR), of Optokinetic Nystagmus (OKN) and of Visuo-Vestibular-Ocular-Reflex (VVOR) in seven normal subjects and in thirty-two patients who had undergone cervical trauma in an automobile accident with the so called "whiplash mechanism". Thirteen subjects underwent examination within the first three months after the accident (first group), six subjects between the third and the sixth months (third group). Ocular movements was recorded according to the usual method by means of a Tonnies electronystagmograph with eight channels. The subjects, head blocked, sat on a Tonnies rotatory chair Pro model which was placed in the middle of a rotatory cylindrical chamber 2 metres in diameter and 1.9 metres in height. The width internal area was covered with thirty-two black vertical contrast. The rotatory cylinder was lighted from above by a 100 W bulb and was driven by a direct current engine which turned it clockwise and counterclockwise up to 200 degrees/sec., maximum speed, with preset acceleration ranging from 1 degree to 2 degrees/sec. All the subjects underwent to Rotatory Vestibular Stimulation by Stop test from a constant angular velocity of 90 degrees/sec. with clockwise and counterclockwise rotation, "stare type" Optokinetic stimulation with a cylinder rotation velocity of 30 degrees/sec. for 60 seconds and to contemporary Rotatory Vestibular and Optokinetic Stimulation (VVOR) so that OKN was VOR counterdirectional. The results of our experience show a statistically significative mean gain decrease of VOR and VVOR nystagmus (beating OKN direction) calculated on the first three beats in the patients of the first group and a significative increase of OKN mean gain in all the patients of the three groups. Furthermore, in sixteen out of thirty-two patients (seven in the first group, two in the second and seven in the third) we observed (during VVOR examination, immediately after stop) a nystagmus beating VOR direction lasting from 3 to 15 seconds.

[Echography in laryngeal tumors]

During sonographic (US) studies of the neck for the nodal staging of patients with laryngeal neoplasms, the authors observed that, especially in advanced cases, also the primary lesion could be imaged with this method. Therefore, US capabilities were investigated in assessing the local stage of laryngeal neoplasms; the results were compared with clinical and surgical findings. Fifty normal subjects of various ages were previously examined to assess the normal US anatomy of laryngeal structures. The presence of calcifications within the thyroid cartilage is the major obstacle to US imaging of the larynx and is directly related to age; indeed, only 40% of subjects can be examined at the age of 70. Seventeen patients with advanced laryngeal tumors were examined by US. Laryngeal imaging was possible, either in part or completely, in 16 of 17 cases. The results were in agreement with clinical staging in 14 cases; in 2 cases US proved clinical understaging by detecting lesion spread to anterolateral perilaryngeal structures. To conclude, US is not suggested as the method of choice in patients with laryngeal neoplasms. However, in subjects with advanced tumors, also US can image the lesion directly, and even detect tumor spread to surrounding tissues, especially in the anterior and lateral directions. In a few cases, this can contribute to preoperative staging and to select the correct therapeutic approach.