Renal Function Assessment Gap in Clinical Practice: An Awkward Truth.

INTRODUCTION: An accurate assessment of renal function is needed in the majority of clinical settings. Unfortunately, the most used estimated glomerular filtration rate (eGFR) formulas are affected by significant errors in comparison to gold standards methods of measured GFR (mGFR). OBJECTIVE: The objective of the study is to determine the extent of the error of eGFR formulas compared to the mGFR in different specific clinical settings. METHODS: A total retrospectively consecutive cohort of 1,320 patients (pts) enrolled in 2 different European Hospitals (Center 1: 470 pts; Center 2: 850 pts) was collected in order to compare the most common eGFR formulas used by physicians with the most widespread mGFR methods in daily clinical practice (Iohexol Plasma Clearance -Center 1 [mGFR-iox] and Renal Scintigraphy -Center 2 [mGFR-scnt]). The study cohort was composed by urological, oncological, and nephrological pts. The agreement between eGFR and mGFR was evaluated using bias (as median of difference), precision (as interquartile range of difference) accuracy (as P30), and total deviation index. RESULTS: The most accurate eGFR formula in the comparison with gold standard method (Iohexol plasma clearance) in Center 1 was represented by s-creatinine and cystatin C combined Chronic Kidney Disease-Epidemiology Collaboration-cr-cy, even though the P30 is reduced (84%) under the threshold of 60 mL/min/1.73 m2. Similar results were found in Center 2, with a wider discrepancy between mGFR-scnt and eGFR formulas due to the minor accuracy of the nuclear tool in respect to the mGFR-iox. CONCLUSIONS: The loss of accuracy observed for the formulas at lower values of GFR suggests the mandatory use of gold standards methods as Iohexol Plasma Clearance to assess the correct status of renal function for critical cases. The center 2 showed lower levels of agreement between mGFR and eGFR suggesting that the errors are partially accounted for the Renal Scintigraphy technique too. In particular, we suggest the use of mGFR-iox in oncological urological and nephrological pts with an eGFR lower than 60 mL/min/1.73 m2.

Development of functionally patent lymphatic meshes in postsurgical long-term resolution of peripheral secondary lymphedema.

OBJECTIVE: In oncologic surgery, secondary lymphedema of male external genital organs and upper or lower limbs frequently develops as a result of excision or mechanical obstruction of collecting lymphatic trunks. We evaluated whether the short-term and long-term outcomes of microsurgical treatment of limb and genital organs improves tissue drainage in patients with secondary lymphedema by restoring the pre-existing lymphatic networks or through new lymphangiogenesis. METHODS: Of 110 secondary lymphedema patients, microsurgery was performed in 45 hospitalized patients. Patients were aged 25 to 75 years, had at least third-degree lymphedema, no satisfactory results from previous physical or pharmacologic therapy, without primitive neoplasia, at least 1 year since the last postsurgical adjuvant oncological treatment, and <15 years since the previous primary oncologic lymphedema development. A microsurgical lymphovenous shunt of the spermatic cord (n = 7), a lymphovenous shunt of the lower limbs (n = 32), or lymphatic grafting of the upper limbs (n = 6) was performed. The male external genitals were treated through an innovative lymphovenous shunt of the lymphatic collectors in the pampiniform plexus of the spermatic cord. For lower limb lymphedema, the lymphatics were shunted to the collaterals or saphenous vein. For upper limb lymphedema, a shunt was performed between the lymph vessels of the jugular-supraclavicular area and those in close continuity with the axillary region. The patency of the new lymphatic pathways was assessed using Photodynamic Eye (Hamamatsu Photonic K.K., Tokyo, Japan) lymphography. RESULTS: Six months postoperatively, 36 responding patients showed an almost complete recovery from secondary lymphedema. Lymphatic meshes, consisting of several lymphatic vessels merging into well-canalized and complex networks developing in the perianastomotic area or between the adjacent proximal anastomotic lymphatic collectors, were commonly observed in patients who positively responded to microsurgery. These complexes were never encountered in nonresponding patients or in normal, nonedematous tissue. CONCLUSIONS: Long-term postsurgical recovery from severe secondary lymphedema requires canalizing the lymphatic collectors along their original flow pattern and developing perianastomotic meshes. Because this phenomenon can be observed with the same characteristics in different tissues, such as the spermatic cord and the inguinocrural, inguinoscrotal, inguinotesticular, and brachial regions, the development of meshes seems to reflect a generalized phenomenon of local lymphangiogenesis triggered by the microsurgical procedure.

High prevalence of (99m)tc-tetrofosmin reverse perfusion pattern in patients with myocardial infarction and angiographically smooth coronary arteries.

BACKGROUND: There are no published data in the literature on the scintigraphic perfusion pattern in patients with myocardial infarction (MI) and normal coronary arteries (NCA). OBJECTIVES: To evaluate myocardial perfusion imaging in a series of patients with MI and NCA. METHODS: Twenty-seven patients who had developed a MI and had NCA were studied. As a control group we included 27 patients with a recent MI and coronary artery disease (CAD). All patients underwent stress/rest tetrofosmin myocardial perfusion SPECT within 6 months from MI. RESULTS: In patients with NCA tetrofosmin stress images revealed 41 hypoperfused segments in 17 patients (63%). On rest images, 13 segments remained unchanged, 4 showed partial reperfusion, 10 normalized and 14 worsened. Additionally, there were 18 new hypoperfused segments in nine patients. Therefore, perfusion worsened at rest in 18 patients (67%) (32 segments). Overall, at rest there were 49 hypoperfused segments in 22 patients (81%). In patients with CAD, stress images revealed 71 hypoperfused segments. On rest images, 39 segments remained unchanged, 16 showed partial reperfusion and 12 normalized. Four segments worsened at rest and only four patients (15%) showed new perfusion defects at rest. CONCLUSIONS: Myocardial perfusion with tetrofosmin might appear considerably worse at rest than at stress in patients with MI and NCA. Specifically, a reverse perfusion pattern in the infarct area is a frequent finding and is likely to be due to residual tissue viability. We postulate that in these patients the hyperemic response to exercise may mask resting underperfusion areas.