Significance of Basal Cell Carcinomas Exhibiting Intravascular Invasion.

ABSTRACT: Intravascular invasion of tumor cells can be associated with metastasis in many cancers. Basal cell carcinomas (BCCs), however, rarely metastasize; therefore, the clinical impact of intravascularly invasive BCC (IVBCC) is currently unclear. Because of these facts and the rarity of IVBCC, questions have arisen on whether IVBCC truly exists. We present 4 cases of IVBCC: one case with obvious tumor islands within immunolabeled blood vessels in the context of advanced disease and 3 cases found incidentally during Mohs micrographic surgery. We discuss the difficulty in studying IVBCC, the idea that it could be due to artifact, and the lack of direct clinical-pathological correlation. Given these challenges, we propose diagnostic criteria for IVBCC to decrease ambiguity for pathological diagnosis. Such criteria may facilitate further studies on the clinical significance of IVBCC.

Peritumoral matrilin-2 staining may be useful in distinguishing basal cell carcinoma from folliculocentric basaloid proliferation.

BACKGROUND: Folliculocentric basaloid proliferation (FBP) is a benign and reactive proliferation which can histopathologically mimic basal cell carcinomas (BCCs). The incidental presence of FBP during the excision of a BCC can occasionally lead to excessive tissue removal. One distinguishing feature of BCCs is that they invade the stroma, whereas FBPs generally do not. METHODS: Matrilin-2 is an extracellular matrix protein associated with tumor invasion, and we compared the expression of matrilin-2 in peritumoral cells of BCC and FBP. RESULTS: We found increased matrilin-2 expression within the peritumoral stroma of 41 of 42 BCCs (97.7%), with strong expression in all (100%) cases of infiltrative subtypes and in 21 of 25 (84%) nodular subtypes of BCC. We found no expression of peritumoral matrilin-2 in any of the seven cases of FBP. CONCLUSION: Our results suggest that immunolabeling with the matrilin-2 antibody may help distinguish BCCs from FBPs.

MOC-31 Antibody Immunolabeling During Mohs Surgery.

BACKGROUND: Ber-EP4 is an antibody that labels basal cell carcinoma (BCC) by targeting epithelial cell adhesion molecule (Ep-CAM). MOC-31, a monoclonal mouse antibody, also targets Ep-CAM and is currently used to differentiate several extracutaneous epithelial tumors. However, the utility of MOC-31 has not been fully described in cutaneous tumors and in Mohs micrographic surgery (MMS). OBJECTIVE: To evaluate MOC-31 labeling in BCC and other cutaneous tumors and to compare immunolabeling intensity of MOC-31 and Ber-EP4 in BCCs. MATERIALS AND METHODS: Nineteen permanently fixed and 29 frozen BCC specimens and 23 other cutaneous tumors were labeled with MOC-31; labeling intensity of tumors, epidermis, and adnexal structures were recorded. In a separate study, a blinded dermatopathologist compared labeling intensities of 8 BCC specimens, each labeled with MOC-31 and Ber-EP4.4. RESULTS: MOC-31 labeled all BCCs. Eccrine coils and follicular bulbs did label variably, although this did not detract utility of MOC-31. Five of thirteen cutaneous squamous cell carcinomas and one of two Merkel cell carcinomas demonstrated MOC-31 positivity. MOC-31 and Ber-EP4 labeled BCCs similarly. CONCLUSION: MOC-31, an antibody directed against Ep-CAM, is sensitive for BCCs in frozen specimens encountered in MMS and permanently fixed specimen. In addition, MOC-31 demonstrated comparable immunolabeling characteristics with Ber-EP4 for BCCs.

High dose genistein in Sanfilippo syndrome: A randomised controlled trial.

The aim of this study was to evaluate the efficacy of high dose genistein aglycone in Sanfilippo syndrome (mucopolysaccharidosis type III). High doses of genistein aglycone have been shown to correct neuropathology and hyperactive behaviour in mice, but efficacy in humans is uncertain. This was a single centre, double-blinded, randomised, placebo-controlled study with open-label extension phase. Randomised participants received either 160 mg/kg/day genistein aglycone or placebo for 12 months; subsequently all participants received genistein for 12 months. The primary outcome measure was the change in heparan sulfate concentration in cerebrospinal fluid (CSF), with secondary outcome measures including heparan sulfate in plasma and urine, total glycosaminoglycans in urine, cognitive and adaptive behaviour scores, quality of life measures and actigraphy. Twenty-one participants were randomised and 20 completed the placebo-controlled phase. After 12 months of treatment, the CSF heparan sulfate concentration was 5.5% lower in the genistein group (adjusted for baseline values), but this was not statistically significant (P = .26), and CSF heparan sulfate increased in both groups during the open-label extension phase. Reduction of urinary glycosaminoglycans was significantly greater in the genistein group (32.1% lower than placebo after 12 months, P = .0495). Other biochemical and clinical parameters showed no significant differences between groups. High dose genistein aglycone (160 mg/kg/day) was not associated with clinically meaningful reductions in CSF heparan sulfate and no evidence of clinical efficacy was detected. However, there was a statistically significant reduction in urine glycosaminoglycans. These data do not support the use of genistein aglycone therapy in mucopolysaccharidosis type III. High dose genistein aglycone does not lead to clinically meaningful reductions in biomarkers or improvement in neuropsychological outcomes in mucopolysaccharidosis type III.

Genotype-phenotype specificity in Menke-Hennekam syndrome caused by missense variants in exon 30 or 31 of CREBBP.

CREBBP loss-of function variants cause Rubinstein-Taybi syndrome (RTS). There have been two separate reports of patients with missense variants in exon 30 or 31 of CREBBP in individuals lacking the characteristic facial and limb dysmorphism associated with RTS. Frequent features in this condition include variable intellectual disability, short stature, autistic behavior, microcephaly, feeding problems, epilepsy, recurrent upper airway infections, and mild hearing impairment. We report three further patients with de novo exon 31 CREBBP missense variants. The first individual has a c.5357G>A p. (Arg1786His) variant affecting the same codon as one of the previously described patients. Both these patients could be recognized by clinicians as mild RTS. Our second patient has a c.5602C>T p.(Arg1868Trp) variant that has been described in five other individuals who all share a strikingly similar phenotype. The third individual has a novel c.5354G>A p.(Cys1785Try) variant. Our reports expand the clinical spectrum to include ventriculomegaly, absent corpus callosum, staphyloma, cochlear malformations, and exomphalos. These additional cases also help to establish genotype-phenotype correlations in this disorder. After the first and last authors of the previous two reports, we propose to call this disorder "Menke-Hennekam syndrome" to establish it as a clinical entity distinct from RTS and to provide a satisfactory name for adoption by parents and professionals, thus facilitating appropriate clinical management and research.

A phase 1/2 study of intrathecal heparan-N-sulfatase in patients with mucopolysaccharidosis IIIA.

OBJECTIVE: This was an open-label, phase 1/2 dose-escalation, safety trial of intrathecal recombinant human heparan-N-sulfatase (rhHNS) administered via intrathecal drug delivery device (IDDD) for treating mucopolysaccharidosis IIIA (NCT01155778). STUDY DESIGN: Twelve patients received 10, 45, or 90mg of rhHNS via IDDD once monthly for a total of 6 doses. Primary endpoints included adverse events (AEs) and anti-rhHNS antibodies. Secondary endpoints included standardized neurocognitive assessments, cortical gray matter volume, and pharmacokinetic/pharmacodynamic analyses. RESULTS: All patients experienced treatment-emergent AEs; most of mild-to-moderate severity. Seven patients reported a total of 10 serious AEs (SAEs), all but one due to hospitalization to revise a nonfunctioning IDDD. No SAEs were considered related to rhHNS. Anti-rhHNS antibodies were detected in the serum of 6 patients and in the cerebrospinal fluid (CSF) of 2 of these. CSF heparan sulfate levels were elevated at baseline and there were sustained declines in all tested patients following the first rhHNS dose. No impact of anti-rhHNS antibodies on any pharmacodynamic or safety parameters was evident. 4 of 12 patients showed a decline in developmental quotient, 6 were stable, and 2 patients had only a single data point. No dose group showed a clearly different response pattern. CONCLUSIONS: rhHNS administration via IDDD appeared generally safe and well tolerated. Treatment resulted in consistent declines in CSF heparan sulfate, suggesting in vivo activity in the relevant anatomical compartment. Results of this small study should be interpreted with caution. Future studies are required to assess the potential clinical benefits of rhHNS and to test improved IDDD models.

Sebelipase alfa over 52 weeks reduces serum transaminases, liver volume and improves serum lipids in patients with lysosomal acid lipase deficiency.

BACKGROUND & AIMS: Lysosomal acid lipase deficiency is an autosomal recessive enzyme deficiency resulting in lysosomal accumulation of cholesteryl esters and triglycerides. LAL-CL04, an ongoing extension study, investigates the long-term effects of sebelipase alfa, a recombinant human lysosomal acid lipase. METHODS: Sebelipase alfa (1mg/kg or 3mg/kg) was infused every-other-week to eligible subjects. Safety and tolerability assessments, including liver function, lipid profiles and liver volume assessment, were carried out at regular intervals. RESULTS: 216 infusions were administered to eight adult subjects through week 52 during LAL-CL04. At week 52, mean alanine aminotransferase and aspartate aminotransferase levels were normal with mean change from baseline of -58% and -40%. Mean changes for low-density lipoprotein, total cholesterol, triglyceride and high-density lipoprotein were -60%, -39%, -36%, and +29%, respectively. Mean liver volume by magnetic resonance imaging and hepatic proton density fat fraction decreased (12% and 55%, respectively). Adverse events were mainly mild and unrelated to sebelipase alfa. Infusion-related reactions were uncommon: three events of moderate severity were reported in two subjects; one patient's event was suggestive of a hypersensitivity-like reaction, but additional testing did not confirm this, and the subject has successfully re-started sebelipase alfa. Of samples tested to date, no anti-drug antibodies have been detected. CONCLUSIONS: Long-term dosing with sebelipase alfa in lysosomal acid lipase-deficient patients is well tolerated and produces sustained reductions in transaminases, improvements in serum lipid profile and reduction in the hepatic fat fraction. A randomized, placebo-controlled phase 3 trial in children and adults is underway (ARISE: NCT01757184).

Clinical effect and safety profile of recombinant human lysosomal acid lipase in patients with cholesteryl ester storage disease.

UNLABELLED: Cholesteryl ester storage disease (CESD), an inherited deficiency of lysosomal acid lipase (LAL), is an underappreciated cause of progressive liver disease with no approved therapy. Presenting features include dyslipidemia, elevated transaminases, and hepatomegaly. To assess the clinical effects and safety of the recombinant human LAL, sebelipase alfa, nine patients received four once-weekly infusions (0.35, 1, or 3 mg·kg(-1) ) in LAL-CL01, which is the first human study of this investigational agent. Patients completing LAL-CL01 were eligible to enroll in the extension study (LAL-CL04) in which they again received four once-weekly infusions of sebelipase alfa (0.35, 1, or 3 mg·kg(-1) ) before transitioning to long-term every-other-week infusions (1 or 3 mg·kg(-1) ). Sebelipase alfa was well tolerated, with mostly mild adverse events unrelated to sebelipase alfa. No antidrug antibodies were detected. Transaminases decreased in patients in LAL-CL01 and increased between studies. In seven patients receiving ongoing sebelipase alfa treatment in LAL-CL04, the mean ± standard deviation (SD) decreases for alanine transaminase and aspartate aminotransferase at week 12 compared to the baseline values in LAL-CL01 were 46 ± 21 U/L (-52%) and 21 ± 14 U/L (-36%), respectively (P ≤ 0.05). Through week 12 of LAL-CL04, these seven patients also showed mean decreases from baseline in total cholesterol of 44 ± 41 mg/dL (-22%; P = 0.047), low density lipoprotein-cholesterol of 29 ± 31 mg/dL (-27%; P = 0.078), and triglycerides of 50 ± 38 mg/dL (-28%, P = 0.016) and increases in high density lipoprotein-cholesterol of 5 mg/dL (15%; P = 0.016). CONCLUSION: These data establish that sebelipase alfa, an investigational enzyme replacement, in patients with CESD is well tolerated, rapidly decreases serum transaminases, and that these improvements are sustained with long-term dosing and are accompanied by improvements in serum lipid profile.

Drug-associated skin lesions in a patient with myelofibrosis receiving ruxolitinib.

Ruxolitinib, a small molecule JAK-1/2 inhibitor, was approved by the U.S. Food and Drug Administration (FDA) in November 2011, as the first therapeutic for the treatment of intermediate and high-risk myelofibrosis. The Janus kinase/signal transducers and activators of transcription (JAK/STAT) pathway is one of the most well-studied intracellular signaling networks. Recent advances in our understanding of the complexities of signal activation and regulation of gene expression has provided opportunities for targeted therapeutic interventions. Although numerous inhibitors of the JAK/STAT pathway are currently being evaluated in clinical trials, ruxolitinib represents the first FDA approved in-class JAK inhibitor. We report a drug eruption associated with ruxolitinib.

Does early use of enzyme replacement therapy alter the natural history of mucopolysaccharidosis I? Experience in three siblings.

Enzyme replacement therapy is widely used as treatment for mucopolysaccharidosis I (MPS I), and there is evidence that this produces improvement in certain clinical domains. There does appear to be variation in the response of clinical features to treatment once these are established. In a reported sibling pair, when enzyme replacement therapy was commenced pre-symptomatically in the younger child, the natural history of the condition appeared to be affected. We present data from three siblings treated with enzyme replacement therapy at different ages which supports this finding.

Design and methods of a postmarketing pharmacoepidemiology study assessing long-term safety of Prolia® (denosumab) for the treatment of postmenopausal osteoporosis.

PURPOSE: To describe the rationale and methods for a prospective, open-cohort study assessing the long-term safety of Prolia(®) for treatment of postmenopausal osteoporosis (PMO) in postmarketing settings. METHODS: Data will be derived from United States Medicare, United Healthcare, and Nordic (Denmark, Sweden, Norway) national registries. Observation will begin on the date of first Prolia(®) regulatory approval (May 26, 2010) and continue for 10 years. Women with PMO will be identified by postmenopausal age, osteoporosis diagnosis, osteoporotic fracture, or osteoporosis treatment. Exposure to Prolia(®) and bisphosphonates will be updated during follow-up; exposure cohorts will be defined based on patient-years during which patients are on- or post-treatment. Nine adverse events (AEs) will be assessed based on diagnosis codes: osteonecrosis of the jaw (ONJ), atypical femoral fracture (AFF), fracture healing complications, hypocalcemia, infection, dermatologic AEs, acute pancreatitis, hypersensitivity, and new primary malignancy. Medical review will confirm selected potential cases of ONJ and AFF. Incidence rates (IRs) of AEs will be described overall and for exposure cohorts; multivariate Cox proportional hazard regression models will compare IRs of AEs across exposure cohorts. Utilization patterns of Prolia(®) for approved, and unapproved indications will be described. CONCLUSION: This study is based on comprehensive preliminary research and considers methodological challenges specific to the study population. The integrated data systems used in this regulatory committed program can serve as a powerful data resource to assess diverse and rare AEs over time.

Primary Cutaneous Gamma-Delta T-cell Lymphoma: A Case Report and Review of Literature.

Primary cutaneous gamma-delta T-cell lymphoma (PCGD-TCL) is a rare type of lymphoma, representing less than 1% of all cutaneous T-cell lymphomas. It is typically aggressive and chemotherapy-refractory. Hence, most institutions tend to employ intensive chemotherapy followed by stem cell transplantation although there is no standard of care established. We report a case of PCGD-TCL and discuss the challenges associated with the diagnosis and management of PCGD-TCL.

Permanent daylight saving time would reduce deer-vehicle collisions.

Overlap between wildlife and human activity is key to causing wildlife-vehicle collisions, a globally pervasive and growing source of wildlife mortality.1,2 Policies regarding clock time often involve abrupt seasonal shifts in human activity, potentially influencing rates of human-wildlife conflict. Here, we harness the biannual shift between standard and daylight saving time as a natural experiment to reveal how the timing of human activity influences deer-vehicle collisions. Based on 1,012,465 deer-vehicle collisions and 96 million hourly traffic observations across the United States, we show that collisions are 14 times more frequent 2 hours after sunset than before sunset, highlighting the importance of traffic during dark hours as a key determinant of deer-vehicle collision risk. The switch from daylight saving to standard time in autumn causes peak traffic volumes to shift from before sunset to after sunset, leading to a 16% spike in deer-vehicle collisions. By reducing traffic after dark, our model predicts that year-round daylight saving time would prevent 36,550 deer (Odocoileus sp.) deaths, 33 human deaths, 2,054 human injuries, and US$1.19 billion in collision costs annually. In contrast, permanent standard time is predicted to increase collisions by an even larger magnitude, incurring an additional US$2.39 billion in costs. By targeting the temporal dimension of wildlife-vehicle collisions, strategies such as year-round daylight saving time that reduce traffic during dark hours, especially during the breeding season of abundant ungulates, would yield substantial benefits for wildlife conservation and reduce the social and economic costs of deer-vehicle collisions.

Chronic kidney disease and the risk of end-stage renal disease versus death.

BACKGROUND: Among older adults with chronic kidney disease (CKD), the comparative event rates of end-stage renal disease (ESRD) and cause-specific death are unknown. OBJECTIVE: To compare the rates of ESRD, cardiovascular and non-cardiovascular death and examine risk factors for ESRD and all-cause mortality in Cardiovascular Health Study (CHS) participants. DESIGN: The CHS is a longitudinal cohort study of community-dwelling adults aged 65 years and older. PARTICIPANTS: 1,268 participants with an estimated glomerular filtration rate (eGFR) < 60 ml/min per 1.73 m(2) were followed until the time of first event (ESRD, cardiovascular or non-cardiovascular death) or until March 31, 2003. MAIN MEASURES: The outcomes were ESRD, cardiovascular- and non-cardiovascular death. Rates of each event were calculated, and a Cox Proportional Hazards Model with a competing risk framework was used to examine risk factors for ESRD as compared with death. Predictors included age, gender, race, BMI, hypertension, diabetes, cardiovascular disease, heart failure, tobacco use, eGFR, and total cholesterol. KEY RESULTS: During 9.7 years of follow-up, 5% of the cohort progressed to ESRD, and 61% of the cohort died. The rate (per 100 person-years) was 0.5 for ESRD and 6.8 for all-cause mortality (3.0 for cardiovascular and 3.8 for non-cardiovascular mortality). In the competing risk framework, lower eGFR, male gender, African-American race, and higher BMI were associated with an increased risk of ESRD. CONCLUSIONS: Older adults with CKD are 13-fold more likely to die from any cause than progress to ESRD and are 6-fold more likely to die from cardiovascular causes than develop ESRD.

Severe hypothyroidism following a single topical exposure to iodine in a premature neonate.

A neonate, born at 24 weeks, underwent a patent ductus arteriosus ligation, with previous normal thyroid stimulating hormone (TSH) levels, developed severe hypothyroidism from topical exposure to iodine following a single surgical procedure at 28 days of life. A low free T4 level of 0.05 ng/dL and a high TSH level of 228 mIU/L was detected with an increased urinary iodine excretion level of 178 mg/L (reference range 0.30-1.97 mg/L). The thyroid ultrasound was normal. Levothyroxine was started immediately but thyroid function did not recover fully during admission and levothyroxine was required beyond term corrected. This case highlighted how susceptible extremely preterm infants are to iodine induced hypothyroidism, even short-term topical exposure. Delayed treatment of hypothyroidism can lead to profound neurodevelopmental delay. As surgical advances allow for interventions at earlier gestations, the importance of early thyroid function testing postexposure to iodine is highlighted and ultimately topical iodine should be avoided in these susceptible infants.

Presynaptic congenital myasthenic syndrome due to three novel mutations in SLC5A7 encoding the sodium-dependant high-affinity choline transporter.

SLC5A7 encodes the presynaptic sodium-dependant high-affinity choline transporter 1 (CHT), which uptakes choline to the presynaptic nerve terminal following the breakdown of acetylcholine by the acetylcholinesterase within the synaptic cleft. We report 5 patients from three consanguineous families with congenital myasthenic syndrome type 20 caused by novel mutations in SLC5A7. The individuals from family 1 and 2 were homozygous for c.320G>A; (p.Arg107His) and c.886G>A (p.Ala296Thr), respectively, and their phenotype was characterised by recurrent apnoeic attacks early after birth and learning and speech difficulties in childhood. Individuals from family 3 were homozygous for c.1240T>A (p.Tyr414Asn) and suffered from more severe central and peripheral manifestations with lack of spontaneous movements and respiratory drive and overall minimal response to external stimuli. All individuals tested showed neurophysiological defects compatible with impaired neuromuscular transmission. Combined treatment with cholinesterase inhibitors and ß2-adrenergic agonists was beneficial in patients from family 1 and 2. Affected individuals from family 3 died from complications directly related to their underlying genetic condition. This report provides three novel pathogenic variants in SLC5A7 and highlights the variability in the clinical phenotype, severity and prognosis of this syndrome.

Characterising a homozygous two-exon deletion in UQCRH: comparing human and mouse phenotypes.

Mitochondrial disorders are clinically and genetically diverse, with isolated complex III (CIII) deficiency being relatively rare. Here, we describe two affected cousins, presenting with recurrent episodes of severe lactic acidosis, hyperammonaemia, hypoglycaemia and encephalopathy. Genetic investigations in both cases identified a homozygous deletion of exons 2 and 3 of UQCRH, which encodes a structural complex III (CIII) subunit. We generated a mouse model with the equivalent homozygous Uqcrh deletion (Uqcrh-/- ), which also presented with lactic acidosis and hyperammonaemia, but had a more severe, non-episodic phenotype, resulting in failure to thrive and early death. The biochemical phenotypes observed in patient and Uqcrh-/- mouse tissues were remarkably similar, displaying impaired CIII activity, decreased molecular weight of fully assembled holoenzyme and an increase of an unexpected large supercomplex (SXL ), comprising mostly of one complex I (CI) dimer and one CIII dimer. This phenotypic similarity along with lentiviral rescue experiments in patient fibroblasts verifies the pathogenicity of the shared genetic defect, demonstrating that the Uqcrh-/- mouse is a valuable model for future studies of human CIII deficiency.

Lysine acetyltransferase 8 is involved in cerebral development and syndromic intellectual disability.

Epigenetic integrity is critical for many eukaryotic cellular processes. An important question is how different epigenetic regulators control development and influence disease. Lysine acetyltransferase 8 (KAT8) is critical for acetylation of histone H4 at lysine 16 (H4K16), an evolutionarily conserved epigenetic mark. It is unclear what roles KAT8 plays in cerebral development and human disease. Here, we report that cerebrum-specific knockout mice displayed cerebral hypoplasia in the neocortex and hippocampus, along with improper neural stem and progenitor cell (NSPC) development. Mutant cerebrocortical neuroepithelia exhibited faulty proliferation, aberrant neurogenesis, massive apoptosis, and scant H4K16 propionylation. Mutant NSPCs formed poor neurospheres, and pharmacological KAT8 inhibition abolished neurosphere formation. Moreover, we describe KAT8 variants in 9 patients with intellectual disability, seizures, autism, dysmorphisms, and other anomalies. The variants altered chromobarrel and catalytic domains of KAT8, thereby impairing nucleosomal H4K16 acetylation. Valproate was effective for treating epilepsy in at least 2 of the individuals. This study uncovers a critical role of KAT8 in cerebral and NSPC development, identifies 9 individuals with KAT8 variants, and links deficient H4K16 acylation directly to intellectual disability, epilepsy, and other developmental anomalies.

The utility of the DNA microarray scanner to simplify the immunofluorescence evaluation of autoimmune bullous diseases.

A DNA microarray scanner was used as a digital fluorescence microscope to simplify the diagnosis of autoimmune bullous diseases. Frozen sections of skin biopsies were taken from 3 patients with bullous pemphigoid and 1 patient each with lichen planus pemphigoides, linear immunoglobulin (Ig) A disease, and dermatitis herpetiformis. After incubation with cyanine-labeled antibodies, the tissues were scanned at 5-mum resolution using an instrument originally designed to study gene expression. The microarray scanner's large field of view, unlike that of fluorescence microscopy, allowed a view of the entire specimen, considerably easing the orientation of tissue. All images were diagnostic and included a linear pattern along the basement membrane zone (BMZ) using anti-IgG and anti-C3 in all cases of bullous pemphigoid, a linear pattern of IgG along the BMZ in lichen planus pemphigoides, and a linear pattern of IgA along the BMZ in linear IgA dermatosis. IgA deposition along dermal papillary tips was seen in dermatitis herpetiformis, but a granular pattern was indiscernible at the 5-mum resolution. The advantages of the microarray scanner over standard fluorescence microscopy include speed, technical ease, large field of view, potential for visualizing multiple antibodies simultaneously in a tissue, and convenience of digital image archiving.

Differences in kidney function and incident hypertension: the multi-ethnic study of atherosclerosis.

BACKGROUND: Kidney disease and hypertension commonly coexist, yet the direction of their association is still debated. OBJECTIVE: To evaluate whether early kidney dysfunction, measured by serum cystatin C levels and urinary albumin excretion, predates hypertension in adults without clinically recognized kidney or cardiovascular disease. DESIGN: Observational cohort study using data from 2000 to 2005. SETTING: The MESA (Multi-Ethnic Study of Atherosclerosis), a community-based study of subclinical cardiovascular disease in adults age 45 to 84 years. PARTICIPANTS: 2767 MESA participants without prevalent hypertension, cardiovascular disease, or clinically recognized kidney disease (an estimated glomerular filtration rate <60 mL/min per 1.73 m2 or microalbuminuria). MEASUREMENTS: Cystatin C was measured by using a nephelometer, and urinary albumin and creatinine were measured from a spot morning collection. The primary outcome was incident hypertension, defined as systolic blood pressure of at least 140 mm Hg, diastolic blood pressure of at least 90 mm Hg, or use of an antihypertensive medication. RESULTS: During a median follow-up of 3.1 years, 19.7% of the cohort (545 participants) developed hypertension. After adjustment for established hypertension risk factors, each 15-nmol/L increase in cystatin C was associated with a statistically significant 15% greater incidence of hypertension (P = 0.017). The highest sex-specific quartile of urinary albumin-creatinine ratio was associated with a statistically insignificant 16% greater incidence of hypertension (P = 0.192) compared with the lowest quartile. No statistical evidence suggested a multiplicative interaction. LIMITATIONS: Unmeasured characteristics may have confounded observed associations of kidney markers with hypertension. Follow-up was relatively short. Hypertension that may have occurred between study visits or hypertension that was not captured by standard cuff measurements may have been missed. CONCLUSION: Differences in kidney function, indicated by cystatin C levels, are associated with incident hypertension among individuals without clinical kidney or cardiovascular disease. These population-based findings complement experimental work implicating early kidney damage in the pathogenesis of essential hypertension.