Heart rate recovery post 6-minute walking test in obstructive sleep apnea: cycle ergometry versus 6-minute walking test in OSA patients.

PURPOSE: To examine the clinical usefulness of heart rate recovery (HRR) post 6-minute walking test (6MWT) as a simple marker of cardiovascular risk in obstructive sleep apnea (OSA) patients in comparison to HRR post cycle ergometry, the validated and more sophisticated protocol. METHODS: Seventy-four participants underwent full overnight polysomnography, cycle ergometry and 6MWT. The HRR at 1, 2 and 3 min (HRR-1, HRR-2 and HRR-3) 6MWT was compared to HRR at 1, 2, and 3 min post cycle ergometry in normal subjects and in moderate and severe OSA patients before and after 6-month CPAP treatment. RESULTS: The HRR-1, HRR-2 and HRR-3 in 6MWT were significantly different between normal, moderate and severe OSA patients with higher rates achieved in normal. The higher the severity of OSA the lower the HRR was. There were also no differences found between work rate and distance walked during cycle ergometry or 6MWT, respectively, concerning normal, moderate and severe OSA patients. Heart rate recovery was further associated with minimum saturation of oxygen during sleep independently of the duration of apnea episodes of BMI and ESS. The treatment with CPAP had a beneficial effect on HRR both post-6MWT and post cycle ergometry. CONCLUSIONS: Autonomic nervous system dysfunction in OSA can be found even with submaximal exertion. Heart rate recovery post-6MWT, such as HRR post cycle ergometry, was significantly impaired in OSA patients in comparison to normals and was favorably influenced from CPAP treatment. Furthermore, it was found to be more sensitive compared with distance walked in 6MWT in discriminating severity of OSA. The HRR post-6MWT was found to be an easily measured and reliable marker of OSA severity both before and after CPAP treatment.

Calprotectin: a protein related to cardiovascular risk in adult patients with obstructive sleep apnea.

INTRODUCTION: Increased levels of inflammatory mediators, such as hs-CRP, have been detected in patients with obstructive sleep apnea (OSA) and used as cardiovascular risk and disease outcome predictors. Calprotectin is an inflammatory marker regulating atherogenic processes not investigated in adult OSA patients. The aim of the present study as primary objective was to examine the role of calprotectin as an inflammatory molecule, acting through a distinct pathway to the atherogenic process in adult OSA patients and its associations with hs-CRP and the lipidemic profile of the patients. As a secondary objective was the evaluation of the atherogenic markers post-CPAP treatment. MATERIALS AND METHODS: Seventy-four participants underwent full overnight polysomnography. Blood samples were collected for calprotectin, hs-CRP, total cholesterol, triglycerides, LDL, HDL and glucose levels. Thirty-two OSA patients were reexamined 6 months post-CPAP treatment. RESULTS: Out of 74 participants included in the study, 33 had moderate OSA, 27 had severe OSA and 14 were controls. Calprotectin and hs-CRP were significantly increased in patients with moderate and severe OSA compared to controls (p<0.0001). Calprotectin and hs-CRP levels were positively correlated with apnea-hypopnea index, BMI and total time of sleep with SaO(2)<90% and inversely correlated with SaO(2) minimum and mean values. Calprotectin and hs-CRP levels were significantly improved post-CPAP treatment (p<0.0001). DISCUSSION: Calprotectin may serve as a novel and reliable, biomarker of cardiovascular risk severity in OSA patients. The decrease of calprotectin levels post-CPAP treatment combined with hs-CRP amelioration could provide evidence for reduction of cardiovascular risk post CPAP treatment.

A case report of Gordon's syndrome in a 20-year-old male with free medical family history.

Gordon's syndrome is a rare autosomal dominant disease that manifests in childhood. It is characterized by hypertension, hyperkalemic hyperchloremic metabolic acidosis, low renin and usually normal aldosterone levels, and it is sensitive to thiazide diuretics. A 20-year-old male with a history of diagnosed Gordon's syndrome was referred to a nephrology clinic for evaluation. The patient, who was under treatment with hydrochlorothiazide, had been diagnosed with Gordon's syndrome at the age of 11, when he presented hypertension and episodes of hyperkalemic hyperchloremic metabolic acidosis. However, none of his relatives had been diagnosed with this syndrome. Therefore, we assume that our patient might be a case of de novo gene mutation.

Fecal calprotectin in pediatric inflammatory bowel disease: a systematic review.

BACKGROUND: Inflammatory bowel disease frequently begins during childhood or adolescence. Current tests and procedures for diagnosing and monitoring inflammatory bowel disease are invasive, uncomfortable and costly. Fecal calprotectin is an inflammatory marker tested in several studies including pediatric patients with inflammatory bowel disease. METHODS: A search for articles published up to October 2011 was conducted using MEDLINE and EMBASE databases. We included original English-written articles referred to pediatric patients with inflammatory bowel disease and measured fecal calprotectin levels. We extracted data concerning fecal calprotectin levels in patients with inflammatory bowel disease and in the controls groups, sensitivity, specificity, positive and negative likelihood ratio. RESULTS: Thirty-four studies were included. Fecal calprotectin levels of patients with inflammatory bowel disease are much higher than those of healthy controls or patients with functional disorders or other gastrointestinal diseases. The results vary greatly when taking all studies into consideration. Nevertheless, in cases of newly diagnosed and/or active inflammatory bowel disease, the results are more homogeneous, with high sensitivity and positive likelihood ratio, low negative likelihood ratio, but moderate specificity. Moreover, 50 µg/g seems to be the most proper cut-off point for the fecal calprotectin test. CONCLUSIONS: The fecal calprotectin test could be used for supporting diagnosis or confirming relapse of inflammatory bowel disease in pediatric patients. A positive result could confirm the suspicion of either inflammatory bowel disease diagnosis or inflammatory bowel disease relapse, due to the high sensitivity of the test, but a negative result should not exclude these conditions, due to its moderate specificity.

Pulmonary aspergilloma: a potential cause of false positive fluorodeoxyglucose positron emission tomography scan.

Pulmonary aspergilloma is a fungus ball developed in a pre-existing lung cavity, generally in the superior lobes. Its size remains stable in most cases and it is usually asymptomatic. Herein, we present a case of a 64-year-old male with pulmonary aspergilloma, which was developed in an emphysematous cyst of the right inferior lobe, increased in size, and fluorodeoxyglucose positron emission tomography scan was positive. There are only a few reported cases of pulmonary aspergilloma with a false positive fluorodeoxyglucose positron emission tomography scan.

Syndromes of impaired ion handling in the distal nephron: pseudohypoaldosteronism and familial hyperkalemic hypertension.

The distal nephron, which is the site of the micro-regulation of water absorption and ion handling in the kidneys, is under the control of aldosterone. Impairment of the mineralocorticoid signal transduction pathway results in resistance to the action of aldosterone and of mineralocorticoids in general. Herein, we review two syndromes in which ion handling in the distal nephron is impaired: pseudohypoaldosteronism (PHA) and familial hyperkalemic hypertension (FHH). PHA is a rare inherited syndrome characterized by mineralocorticoid resistance, which leads to salt loss, hypotension, hyperkalemia and metabolic acidosis. There are two types of this syndrome: a renal (autosomal dominant) type due to mutations of the mineralocorticoid receptor (MR), and a systemic (autosomal recessive) type due to mutations of the epithelial sodium channel (ENaC). There is also a transient form of PHA, which may be due to urinary tract infections, obstructive uropathy or several medications. FHH is a rare autosomal dominant syndrome, characterized by salt retention, hypertension, hyperkalemia and metabolic acidosis. In FHH, mutations of WNK (with-no-lysine kinase) 4 and 1 alter the activity of several ion transportation systems in the distal nephron. The study of the pathophysiology of PHA and FHH greatly elucidated our understanding of the renin-angiotensin-aldosterone system function and ion handling in the distal nephron. The physiological role of the distal nephron and the pathophysiology of diseases in which the renal tubule is implicated may hence be better understood and, based on this understanding, new drugs can be developed.

The role of calprotectin in obstetrics and gynecology.

The purpose of this article is to create the first complete review concerning the role of calprotectin, a calcium- and zinc-binding protein of the S100/calgranulins family, in obstetrics and gynecology. A Medline search was conducted between 6 and 8 June 2009 using the term calprotectin and its synonyms combined with the following ones: calprotectin, obstetrics and gynecology, breast cancer, ovarian cancer, endometrial cancer, cervical cancer, menstrual cycle, pregnancy, fetal implantation, labor, intra-amniotic inflammation, preeclampsia, HELLP syndrome, Rh(-) incompatibility. We found 46 studies which referred to obstetrics and gynecology. We excluded 11 studies which referred to obstetrics and gynecology but did not include enough information about calprotectin, and another two which referred to calprotectin but were not related to subjects of obstetrics and gynecology. Thus, we ended up with 33 studies which contained sufficient information to extract data for this review. All the articles were written in English. It was found that calprotectin is associated with many physiologic and pathologic processes in obstetrics and gynecology, such as: breast cancer, ovarian cancer, endometrial cancer, cervical cancer, cervical and vaginal physiology, menstrual cycle, pregnancy and labor. The role of calprotectin in these conditions is significant. In conclusion, the role of calprotectin seems to be important in several issues of obstetrics and gynecology. For example, calprotectin could be used as a diagnostic, prognostic or metastatic marker in several types of cancer, as a marker of inflammation and as a pharmaceutical target in many conditions. Further studies must be conducted to elucidate this role.