The Friday evening case of acute kidney injury: a crystal dilemma.

We report a case of acute kidney injury (AKI) induced by amoxycillin crystalluria suggested by massive amounts of urinary crystals of unusual morphology. This hypothesis was further reinforced by a particular solubility pattern when the urine sample was exposed to various temperatures, alkali, acids and alcohol. We therefore suspended amoxycillin, which produced a rapid and complete recovery of kidney function. Infrared spectroscopy later confirmed the amoxycillin composition of the crystals. Since infrared spectroscopy is not easily available, we propose that these solubility tests of urinary crystals be used as a first-step investigation when amoxycillin crystalluria is suspected.

[Antimicrobials : some practical considerations]. / Antibiotiques : quelques considérations pratiques.

Antibiotics are frequently prescribed in hospitalized and in outpatients. We review four important aspects for their daily prescription. In elderly patients, the prescription should take into account changes in the volume of distribution and the usual decline in renal function even in the absence of chronic kidney disease. Particular antibiotics can trigger infection with Clostridium difficile. We discuss actual and novel strategies for its prevention. Renal toxicity of antibiotics includes acute tubular necrosis, interstitial nephritis and crystals obstructing renal tubule, depending on the class of antibiotics. Plasmatic levels of particular antibiotics should be measured either at trough or at peak levels depending of the antibiotic prescribed.

Les antibiotiques sont fréquemment prescrits en hospitalier et en ambulatoire. Nous revoyons quatre aspects ayant des conséquences dans la prescription au quotidien. Dans la population âgée, il convient de tenir compte du changement du volume de distribution et du déclin de la fonction rénale même en l'absence de pathologie rénale. L'infection à Clostridium difficile est favorisée par certains antibiotiques en particulier. Afin de la prévenir, nous discuterons des stratégies connues et nouvelles. La toxicité rénale se manifeste selon la classe d'antibiotiques par une nécrose tubulaire aiguë, une néphrite interstitielle ou une cristallurie entraînant une obstruction intratubulaire. Pour certains antibiotiques, la mesure des taux plasmatiques résiduels ou au pic est nécessaire.

[New therapeutics]. / Nouvelles thérapeutiques.

Daily medical practice triggers reflexes in the use of drugs which must nevertheless always be adapted to new knowledge. Physician assistants and residents in the clinical ward of Internal Medicine of Sion Hospital summarize six recently published clinical treatments to which primary care physicians or in hospital-based internal medicine have to pay a particular attention. Quinolones are widely used but associated with QT interval widening, morphine delays and attenuate ticagrelor action in patients with myocardial infarction, evolocumab, a monoclonal antibody impact in reducing lipids and cardiovascular events, impact of statins on influenza vaccine effectiveness, vitamin D treatment for the prevention of functional decline, high dose dexamethasone for the treatment of immune thrombocytopenia.

La pratique médicale quotidienne suscite des réflexes dans l'utilisation de médicaments qui doivent sans cesse être adaptés aux nouvelles connaissances. Les médecins du Service de médecine interne de Sion résument six publications sur des traitements auxquels le praticien ambulatoire ou hospitalier doit porter une attention particulière. L'effet des quinolones sur l'intervalle QT, l'administration concomitante de morphine et de ticagrélor en cas de syndrome coronarien aigu, la place d'un anticorps monoclonal pour abaisser le taux de cholestérol, l'impact des statines sur l'efficacité vaccinale, la rôle de la vitamine D à haute dose pour ralentir le déclin de la performance physique, le stéroïde de choix en cas de thrombopénie auto-immune.

[General internal medicine in hospital practice: the year 2013 put into perspective by residents]. / Médecine interne générale en pratique hospitalière: l'année 2013 mise en perspective par les chefs de clinique.

2013 was full of significant advances in all areas of medicine, which may have an impact on daily practice in general internal medicine. From salt and water restriction in heart failure to transfusion threshold in upper gastrointestinal bleeding and fecal infusion in Clostridium difficile colitis; from new data in resuscitation and persistent questions in palliative care and intensive care medicine, through pneumology, nephrology and endocrinology, the literature has been rich in new considerations. Each year, the residents of the Department of internal medicine of the University hospital of Vaud (CHUV) meet to share their most interesting readings. Thirteen of them are reviewed and commented here.

Cardiovascular responses to water drinking: does osmolality play a role?

Water drinking activates the autonomic nervous system and induces acute hemodynamic changes. The actual stimulus for these effects is undetermined but might be related to either gastric distension or to osmotic factors. In the present study, we tested whether the cardiovascular responses to water drinking are related to water's relative hypoosmolality. Therefore, we compared the cardiovascular effects of a water drink (7.5 ml/kg body wt) with an identical volume of a physiological (0.9%) saline solution in nine healthy subjects (6 male, 3 female, aged 26 +/- 2 years), while continuously monitoring beat-to-beat blood pressure (finger plethysmography), cardiac intervals (electrocardiography), and cardiac output (thoracic impedance). Total peripheral resistance was calculated as mean blood pressure/cardiac output. Cardiac interval variability (high-frequency power) was assessed by spectral analysis as an index of cardiac vagal tone. Baroreceptor sensitivity was evaluated using the sequence technique. Drinking water, but not saline, decreased heart rate (P = 0.01) and increased total peripheral resistance (P < 0.01), high-frequency cardiac interval variability (P = 0.03), and baroreceptor sensitivity (P = 0.01). Neither water nor saline substantially increased blood pressure. These responses suggest that water drinking simultaneously increases sympathetic vasoconstrictor activity and cardiac vagal tone. That these effects were absent after drinking physiological saline indicate that the cardiovascular responses to water drinking are influenced by its hypoosmotic properties.