Cystatin C is a protein produced by all nucleated cells at a constant rate and freely filtered by the kidneys without reabsorption, making it a sensitive marker of glomerular filtration rate (GFR). The document discusses the history, properties, and roles of cystatin C. It notes that cystatin C levels are increased in reduced kidney function and various diseases, and are less influenced by non-renal factors than creatinine. The document also describes methods for measuring cystatin C levels and calculating GFR, limitations of creatinine as a GFR marker, and advantages of using cystatin C to detect chronic kidney disease.
Cystatin C - Early Risk Assessment of Renal Impairment MAY18Randox Reagents
Cystatin C is a small (13 kDa) cysteine proteinase inhibitor, produced by all nucleated cells at a constant rate. Cystatin C travels through the bloodstream to the kidneys where it is freely filtered by the glomerular membrane, resorbed and fully catabolised by the proximal renal tubes. Consequently, Cystatin C is the ideal biomarker of GFR function.
Cystatin C - Early Risk Assessment of Renal Impairment MAY18Randox Reagents
Cystatin C is a small (13 kDa) cysteine proteinase inhibitor, produced by all nucleated cells at a constant rate. Cystatin C travels through the bloodstream to the kidneys where it is freely filtered by the glomerular membrane, resorbed and fully catabolised by the proximal renal tubes. Consequently, Cystatin C is the ideal biomarker of GFR function.
Progression of Chronic Kidney Disease: Mechanisms and Interventions in Retard...Apollo Hospitals
The incidence ofchronickidneydisease (CKD) is increasingworldwideandisbecoming a major concern for the healthcare. Approximately 1.8 million people, worldwide, are currently treated with renal replacement therapy (RRT), which consists primarily of kidney transplantation,
hemodialysis, and peritoneal dialysis.
"End Stage Renal Disease:Common Problems and Possible Solutions". A review of Diabetes and hypertension and how they contribute to complications in the ESRD patient. Renal Care Partners offers state of the art hemodialysis on the campus of Palm Garden of West Palm Beach.
CHRONIC KIDNEY DISEASE- A CASE STUDY IN AYURVEDIC SETTING.VIKAS NARIYAAL
Chronic kidney diseases CKD encompasses a spectrum of different pathophysiologic proCesses associated with abnormal kidney function and a progressive decline in glomerular filtration rate (GFR)
Introduction to Chronic Kidney Disease epidemiology, diagnosis, treatment of complications and system issues (e.g. interface between nephrology and primary care, specialty referrals) for medical students
Accuracy of Laboratory Parameters in Management of CKD and NCDRavi Kumudesh
New model for Health care delivery is suggesting to replace traditional health care organisational structure in Sri Lanka. This type of innovation is essential for "Non Patient" type healthcare receivers, such as "Healthy healthcare receivers" and "Risk Groups".
This topic is inspired by Secretary, CMLS.SL at the Annual Academic Sessions of DiASL on April 22, 2017.
CMLS.SL - College of Medical Laboratory Science, Sri Lanka
DiASL - Dietetic Association of Sri Lanka
Progression of Chronic Kidney Disease: Mechanisms and Interventions in Retard...Apollo Hospitals
The incidence ofchronickidneydisease (CKD) is increasingworldwideandisbecoming a major concern for the healthcare. Approximately 1.8 million people, worldwide, are currently treated with renal replacement therapy (RRT), which consists primarily of kidney transplantation,
hemodialysis, and peritoneal dialysis.
"End Stage Renal Disease:Common Problems and Possible Solutions". A review of Diabetes and hypertension and how they contribute to complications in the ESRD patient. Renal Care Partners offers state of the art hemodialysis on the campus of Palm Garden of West Palm Beach.
CHRONIC KIDNEY DISEASE- A CASE STUDY IN AYURVEDIC SETTING.VIKAS NARIYAAL
Chronic kidney diseases CKD encompasses a spectrum of different pathophysiologic proCesses associated with abnormal kidney function and a progressive decline in glomerular filtration rate (GFR)
Introduction to Chronic Kidney Disease epidemiology, diagnosis, treatment of complications and system issues (e.g. interface between nephrology and primary care, specialty referrals) for medical students
Accuracy of Laboratory Parameters in Management of CKD and NCDRavi Kumudesh
New model for Health care delivery is suggesting to replace traditional health care organisational structure in Sri Lanka. This type of innovation is essential for "Non Patient" type healthcare receivers, such as "Healthy healthcare receivers" and "Risk Groups".
This topic is inspired by Secretary, CMLS.SL at the Annual Academic Sessions of DiASL on April 22, 2017.
CMLS.SL - College of Medical Laboratory Science, Sri Lanka
DiASL - Dietetic Association of Sri Lanka
Accuracy of Laboratory Parameters in Management of CKD.Ravi Kumudesh
New model for Health care delivery is suggesting to replace traditional health care organisational structure in Sri Lanka. This type of innovation is essential for "Non Patient" type healthcare receivers, such as "Healthy healthcare receivers" and "Risk Groups".
This topic is inspired by Secretary, CMLS.SL at the Annual Academic Sessions of DiASL on April 22, 2017.
CMLS.SL - College of Medical Laboratory Science, Sri Lanka
DiASL - Dietetic Association of Sri Lanka
A limited presentation about a) age related renal functional changes b) management of CKD, including advance care planning and transplantation referral c) management of potentially risky drugs in the elderly with CKD (NOACs)
Geriatric Nephrology (changes in renal physiology, Chronic Kidney Disease, Advanced Care Planning for the elderly patients with CKD, pharmacotherapy of common medical problems in the older individual with chronic kidney disease)
Title: Sense of Taste
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the structure and function of taste buds.
Describe the relationship between the taste threshold and taste index of common substances.
Explain the chemical basis and signal transduction of taste perception for each type of primary taste sensation.
Recognize different abnormalities of taste perception and their causes.
Key Topics:
Significance of Taste Sensation:
Differentiation between pleasant and harmful food
Influence on behavior
Selection of food based on metabolic needs
Receptors of Taste:
Taste buds on the tongue
Influence of sense of smell, texture of food, and pain stimulation (e.g., by pepper)
Primary and Secondary Taste Sensations:
Primary taste sensations: Sweet, Sour, Salty, Bitter, Umami
Chemical basis and signal transduction mechanisms for each taste
Taste Threshold and Index:
Taste threshold values for Sweet (sucrose), Salty (NaCl), Sour (HCl), and Bitter (Quinine)
Taste index relationship: Inversely proportional to taste threshold
Taste Blindness:
Inability to taste certain substances, particularly thiourea compounds
Example: Phenylthiocarbamide
Structure and Function of Taste Buds:
Composition: Epithelial cells, Sustentacular/Supporting cells, Taste cells, Basal cells
Features: Taste pores, Taste hairs/microvilli, and Taste nerve fibers
Location of Taste Buds:
Found in papillae of the tongue (Fungiform, Circumvallate, Foliate)
Also present on the palate, tonsillar pillars, epiglottis, and proximal esophagus
Mechanism of Taste Stimulation:
Interaction of taste substances with receptors on microvilli
Signal transduction pathways for Umami, Sweet, Bitter, Sour, and Salty tastes
Taste Sensitivity and Adaptation:
Decrease in sensitivity with age
Rapid adaptation of taste sensation
Role of Saliva in Taste:
Dissolution of tastants to reach receptors
Washing away the stimulus
Taste Preferences and Aversions:
Mechanisms behind taste preference and aversion
Influence of receptors and neural pathways
Impact of Sensory Nerve Damage:
Degeneration of taste buds if the sensory nerve fiber is cut
Abnormalities of Taste Detection:
Conditions: Ageusia, Hypogeusia, Dysgeusia (parageusia)
Causes: Nerve damage, neurological disorders, infections, poor oral hygiene, adverse drug effects, deficiencies, aging, tobacco use, altered neurotransmitter levels
Neurotransmitters and Taste Threshold:
Effects of serotonin (5-HT) and norepinephrine (NE) on taste sensitivity
Supertasters:
25% of the population with heightened sensitivity to taste, especially bitterness
Increased number of fungiform papillae
The prostate is an exocrine gland of the male mammalian reproductive system
It is a walnut-sized gland that forms part of the male reproductive system and is located in front of the rectum and just below the urinary bladder
Function is to store and secrete a clear, slightly alkaline fluid that constitutes 10-30% of the volume of the seminal fluid that along with the spermatozoa, constitutes semen
A healthy human prostate measures (4cm-vertical, by 3cm-horizontal, 2cm ant-post ).
It surrounds the urethra just below the urinary bladder. It has anterior, median, posterior and two lateral lobes
It’s work is regulated by androgens which are responsible for male sex characteristics
Generalised disease of the prostate due to hormonal derangement which leads to non malignant enlargement of the gland (increase in the number of epithelial cells and stromal tissue)to cause compression of the urethra leading to symptoms (LUTS
Report Back from SGO 2024: What’s the Latest in Cervical Cancer?bkling
Are you curious about what’s new in cervical cancer research or unsure what the findings mean? Join Dr. Emily Ko, a gynecologic oncologist at Penn Medicine, to learn about the latest updates from the Society of Gynecologic Oncology (SGO) 2024 Annual Meeting on Women’s Cancer. Dr. Ko will discuss what the research presented at the conference means for you and answer your questions about the new developments.
Couples presenting to the infertility clinic- Do they really have infertility...Sujoy Dasgupta
Dr Sujoy Dasgupta presented the study on "Couples presenting to the infertility clinic- Do they really have infertility? – The unexplored stories of non-consummation" in the 13th Congress of the Asia Pacific Initiative on Reproduction (ASPIRE 2024) at Manila on 24 May, 2024.
These simplified slides by Dr. Sidra Arshad present an overview of the non-respiratory functions of the respiratory tract.
Learning objectives:
1. Enlist the non-respiratory functions of the respiratory tract
2. Briefly explain how these functions are carried out
3. Discuss the significance of dead space
4. Differentiate between minute ventilation and alveolar ventilation
5. Describe the cough and sneeze reflexes
Study Resources:
1. Chapter 39, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 34, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 17, Human Physiology by Lauralee Sherwood, 9th edition
4. Non-respiratory functions of the lungs https://academic.oup.com/bjaed/article/13/3/98/278874
Knee anatomy and clinical tests 2024.pdfvimalpl1234
This includes all relevant anatomy and clinical tests compiled from standard textbooks, Campbell,netter etc..It is comprehensive and best suited for orthopaedicians and orthopaedic residents.
Ozempic: Preoperative Management of Patients on GLP-1 Receptor Agonists Saeid Safari
Preoperative Management of Patients on GLP-1 Receptor Agonists like Ozempic and Semiglutide
ASA GUIDELINE
NYSORA Guideline
2 Case Reports of Gastric Ultrasound
Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
263778731218 Abortion Clinic /Pills In Harare ,sisternakatoto
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New Drug Discovery and Development .....NEHA GUPTA
The "New Drug Discovery and Development" process involves the identification, design, testing, and manufacturing of novel pharmaceutical compounds with the aim of introducing new and improved treatments for various medical conditions. This comprehensive endeavor encompasses various stages, including target identification, preclinical studies, clinical trials, regulatory approval, and post-market surveillance. It involves multidisciplinary collaboration among scientists, researchers, clinicians, regulatory experts, and pharmaceutical companies to bring innovative therapies to market and address unmet medical needs.
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Ve...kevinkariuki227
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
Tom Selleck Health: A Comprehensive Look at the Iconic Actor’s Wellness Journeygreendigital
Tom Selleck, an enduring figure in Hollywood. has captivated audiences for decades with his rugged charm, iconic moustache. and memorable roles in television and film. From his breakout role as Thomas Magnum in Magnum P.I. to his current portrayal of Frank Reagan in Blue Bloods. Selleck's career has spanned over 50 years. But beyond his professional achievements. fans have often been curious about Tom Selleck Health. especially as he has aged in the public eye.
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Introduction
Many have been interested in Tom Selleck health. not only because of his enduring presence on screen but also because of the challenges. and lifestyle choices he has faced and made over the years. This article delves into the various aspects of Tom Selleck health. exploring his fitness regimen, diet, mental health. and the challenges he has encountered as he ages. We'll look at how he maintains his well-being. the health issues he has faced, and his approach to ageing .
Early Life and Career
Childhood and Athletic Beginnings
Tom Selleck was born on January 29, 1945, in Detroit, Michigan, and grew up in Sherman Oaks, California. From an early age, he was involved in sports, particularly basketball. which played a significant role in his physical development. His athletic pursuits continued into college. where he attended the University of Southern California (USC) on a basketball scholarship. This early involvement in sports laid a strong foundation for his physical health and disciplined lifestyle.
Transition to Acting
Selleck's transition from an athlete to an actor came with its physical demands. His first significant role in "Magnum P.I." required him to perform various stunts and maintain a fit appearance. This role, which he played from 1980 to 1988. necessitated a rigorous fitness routine to meet the show's demands. setting the stage for his long-term commitment to health and wellness.
Fitness Regimen
Workout Routine
Tom Selleck health and fitness regimen has evolved. adapting to his changing roles and age. During his "Magnum, P.I." days. Selleck's workouts were intense and focused on building and maintaining muscle mass. His routine included weightlifting, cardiovascular exercises. and specific training for the stunts he performed on the show.
Selleck adjusted his fitness routine as he aged to suit his body's needs. Today, his workouts focus on maintaining flexibility, strength, and cardiovascular health. He incorporates low-impact exercises such as swimming, walking, and light weightlifting. This balanced approach helps him stay fit without putting undue strain on his joints and muscles.
Importance of Flexibility and Mobility
In recent years, Selleck has emphasized the importance of flexibility and mobility in his fitness regimen. Understanding the natural decline in muscle mass and joint flexibility with age. he includes stretching and yoga in his routine. These practices help prevent injuries, improve posture, and maintain mobilit
4. HISTORY
• It was first described as “gamma trace in 1961 as a
trace protein together with other ones (such as beta
trace) in CSF and in urine of patient with renal failure.
• Grubb and Lofberg first reported its amino acid
sequence.
• They noticed it was increased in patient of CRF.
• It was first proposed as a measure of GFR by Grubb
and co-workers in 1985
5. CYSTATIN C
• Cystatin C is a small 13 kDa protein (most potent inhibitor of
cysteine proteases).
• Constant production rate, regulated via house-keeping gene
• Not influenced by muscle mass , or inflammation
• Free renal filtration
• No tubular secretion
• Tubular reabsorption followed by degradation.
6. • The family 3 Cystatins, high and low molecular weight
kininogen, contain three Cystatin domains and are mainly
intravascular proteins, which in addition to being inhibitors of
cysteine proteases also are involved in the coagulation
process and in the production of vasoactive peptides.
• Cystatin C is abundant in various tissues and bodily fluids,
the highest levels having been determined in cerebrospinal
fluid, seminal fluid, plasma, and synovial fluid.
CYSTATIN C
7. PROTEIN TURNOVER
• Half life (N-END RULE).
• Protein with N-Terminal Met,Ser,Thy,Val, or Gly.
Have half life more than 20 hours.
• Protein with N-Terminal Phe,Leu,Asp,Lys, or Arg.
Half life of 3 minutes or less.
• PEST: Proteins with Pro(P),Glu (E),Serine (S)
Thr(T) are more rapidly degraded.
8. CYSTEINE PROTEASES
• Papain is well studied plant (CP).
• Cathepsins are large family of lysosomal cysteine
proteases.
• Caspase are involved in activation & implementation
of Apoptosis..
• Calpains are Ca++ activated cysteine proteases that
cleave intracellular proteins.
• They regulate processes such as cell migration and
wound healing.
9. PROTEASES
• Exoproteases.
• Endoproteases.
• Sereine proteases.
• Cysteine proteases.
• Aspartyl proteases.
• Metal ion proteases (Zn++)
• Threonine proteases.
• *Best substrate is unfolded proteins.
10. CYSTATIN C
• The human Cystatin family presently comprises 11 identified
proteins.
• Two of these, Cystatin A and B, form the family 1 Cystatin
and are mainly, or exclusively, intracellular proteins, while
Cystatin C, D, E, F, S, SA and SN are mainly extracellular
and/or transcellular proteins and constitute the family 2
Cystatins.
• The family 3 cystatins are mainly intravascular proteins,
produces vasoactive peptide & involved in coagulation.
11. FATE OF CYSTATIN-C
• Produced by all nucleated cells and its rate of
production is constant.
• In human, all cells with nucleus produce cystatin
C as a chain of 120 amino acids
• It is freely filtered at the Glomerulus.
• Practically completely reabsorbed by proximal
renal tubules.
• It is totally catabolized in the proximal renal
tubule.
• No re-entry into circulation.
FATE OF CYSTATIN C
12. MOLECULAR BIOLOGY
• Cystatin superfamily encompasses proteins that contain
multiple cystatin like sequences
• Some members are active cysteine proteinase inhibitors
• There are 3 inhibitory families in the superfamily:
1) Type 1 cystatins (stefins)
2) Type 2 cystatins
3) Kininogens
• Type 2 are a class of cysteine proteinase inhibitors found in
human fluids and are protective in function
13. SOME FACTS ABOUT CYSTATIN-C
• Cystatin-C is a non glycosylated basic protein (isoelectric pH 9.3)
• It has a crystal structure characterized by short alpha helix and a
long alpha helix running across a large anti-parallel 5 stranded beta
sheet
• It has 2 disulfide bonds
• 50% of the molecule carry a hydroxylated proline
• It forms two dimers
• It is a potent inhibitor of lysosomal proteinases
• It is also an important inhibitor of extracellular cysteine proteases
• It has a low molecular weight of 13.3 kilodaltons
14. Types of cystatin
• The human cystatin family presently comprises of 11 identified
proteins.
• FAMILY 1: Two cystatin A and B, and are mainly, or exclusively,
intracellular proteins,
• FAMILY 2: C, D, E, F, S, SA and SN are mainly extracellular
and/or transcellular proteins and constitute the family 2 Cystatins.
• Family 3 cystatins: high and low molecular weight kininogen,
contain three cystatin domain & are mainly intravascular proteins.
• In addition to inhibitors of cysteine protease also involved in
coagulation.
15. CALCULATION OF GFR
• CKD-EPI cystatin equation adjusted for age,
sex and race:
• Formula for calculation of eGFR:
• eGFR = 127.7 X (Cys C)-1.17 X (age)-0.13 X
0.91 (if female) X 1.06 (if African American)
CALCULATION OF GFR
16. ROLE IN MEDICINE
• KIDNEY FUNCTION
– It is removed from bloodstream by glomerular
filtration by kidneys
– If the function of kidneys decrease and GFR
falls, level of cystatin-C in blood increases
– So it has been suggested that cystatin-C might
predict the development of CRF
17. ROLE IN MEDICINE (CONT.)
• Levels of cystatin-C are altered in following conditions
1) Cancer patient
2) Thyroid dysfunction
3) Glucocorticoid therapy
4) Cigarette smoking
5) HIV infection
6) Increased levels in MI,stroke,heart failure,peripheral arterial syndrome
7) Increased in metabolic syndrome
8) Increased in Alzheimers disease
9) Levels decreased in atherosclerosis and aneurysmal(saccular bulging)
lesions of aorta
18. • A reliable marker of GFR in patients with mild-to-moderate
kidney dysfunction (stages 2–3 of CKD) in both type 1 and
type 2 diabetes.
• Elevated serum cystatin C levels identified as a significant
prognostic indicator for the development of cardiovascular
disease in people with diabetes.
• Cystatin C is not only a better indicator of GFR in diabetes, it
has the best correlation with changes in GFR over two
years, making it a useful measure for follow-up of patients
with diabetes.
DIABETES MELLITUS
19. HUMAN IMMUNODEFICIENCY
VIRUS (HIV) INFECTION
• Studies have reported increased cystatin C
levels in HIV.
• Because of an increase of cystatin C levels
with active HIV infection, an overestimation of
kidney impairment may occur, particularly in
treatment-naive patients with renal disease.
20. • Like creatinine concentrations, cystatin C
levels are also lower in the hypothyroid and
higher in the hyperthyroid state as compared
with the euthyroid state.
Thyroid Function
21. CARDIOVASCULAR DISEASE
• Cystatin C has been reported to be a potent predictor
of cardiovascular mortality beyond classical risk factors
in patients with CAD and normal or mildly reduced
kidney function.
• Serum cystatin C may have a stronger association
with mortality and cardiovascular disease than
serum creatinine in patients without CKD, as
reported in a large study of older adults.
22. OBESITY
• Serum cystatin C concentrations are increased in human
obesity in relation to over-production by the adipose tissue.
So, cystatin C levels are higher in obese subjects as
compared to lean.
• Adipose tissue is a source of cystatin C in a way that is not
related to eGFR but to the status of adipose tissue itself,
including enlarged adipocytes, hypoxia, pro-inflammatory
cytokines production, increased number of macrophages,
and probably other cellular and molecular alterations known
to occur in obesity
23. METHODS FOR GFR ESTIMATION
GFR measurement Creatinine Cystatin C
Direct measurement
( reference method)
• Clearance
determination by
exogenous
substances
- inulin
- iohexol
- 51Cr-EDTA
- 125 I-iothalamate
not routinely USED
• costly
• time & labor intensive
- invasive, stress-full
for patient
•Small molecule, 113
D
( breakdown product
of creatine as part of
muscle metabolism)
• Routine clinical
chemistry method
- Jaffe method
-enzymatic method
•different formulas for
eGFR, e.g. MDRD
• Small protein, 13
kD
•Cysteine protease
Inhibitor
• Fully automated
immuno-assays
Available
•Method of
standardization
program in
progress.
•Different formulas
for
24. CYSTATIN C
• HIGHLY SENSITIVE
• SPECIFIC MARKER
• CHRONIC KIDNEY DISEASE
• ACUTE RENAL FAILURE
• CARDIOVASCULAR EVENTS
• ALL CAUSE MORTALITY
prognostic
marker
• HEART FAILURE
• STROKE
• DIABETES
• UNSUCCESSFUL AGING
25. CKD – a silent threat
Kidneys do not hurt!
• Laboratory testing = key to early diagnosis
• Prevention as more efficient as earlier
started
• Sensitive detection method required
• Continuous strong increase in the prevalence
of chronic kidney disease
CKD – a silent threat
26. CKD – a silent threat
• Outcomes of CKD:
- progression of renal disease to end-stage renal
disease (ESRD)
• Complications of CKD:
- hypertension
- anemia
- bone and mineral disease
- increased risk of cardiovascular disease
(CVD)
27. IN Seniors
• GFR declines with age and cystatin C may
better reflect true kidney function in older
people because muscle mass does not
influence it.
• After age 50, reference values of serum
cystatin C concentration are higher.
28. IN OBSTETRICS
• Serum cystatin C concentration varies in
pregnancy, because it is not consistently
produced.
• In preeclampsia, however, altered kidney
function is more likely to be detected by CysC–
GFR than by creatinine-based formulas.
29. IN PEDIATRICS
• After age 1, serum cystatin C concentration is
constant, but higher values are found in the
newborn period. In full-term newborns, cystatin C
progressively declines over the first week of life.
• CysC–GFR has been reported to be more accurate
in children with cancer and in patients with spina
bifida.
36. LIMITATIONS OF CREATININE AS A MARKER OF GFR
• NON RENAL FACTORS-
1) Gender
2) Ethinicity
3) Diet
4) Muscle mass
5) Drugs affecting tubular secretion of creatinine
• CLINICAL FACTOR-
– Poor sensitivity for CKD- Creatinine blind range
– Creatinine remains normal until 50% renal function is lost
– Insensitive to loss of GFR in Stage-2 and Stage-3 in CKD
• ANALYTICAL FACTOR-
• Non specific bias frequently reported with Jaffe Assay
37. ADVANTAGE OF CYSTATIN-C AS GFR MARKER
ADVANTAGE COMMENT
Virtually unaffected by non
renal factors
Muscle
mass/weight/height,age(>1
year)-cystatin-c parallels age
related decrease in GFR and
can be used in children
Sensitive to so called creatinine
blind range
Enables early detection and
treatment of CKD
Can be used to detect and
monitor kidney diseases in
patient with hepatic diseases
Creatinine for GFR in liver
disease not recommended
Correlates to appearance of
microalbuminuria
Clinical studies suggest that
very early renal failure may be
the first clinical indication of
progressive renal damage
associated with diabetes
38. CONTRAINDICATION OF CYSTATIN-C
ESTIMATION
• THYROID FUNCTION
• Levels of cystatin-C are sensitive to change in
thyroid function and should not be performed
without knowledge of patients thyroid status
• CORTICOSTEROIDS
• Cystatin-C concentrations are affected in
patients of impaired renal function receiving
corticosteroids
39. LABORATORY MEASUREMENT
• ASSAY PRINCIPLE-
– Cystatin-c in the sample binds to the specific anticystatin-c antibody which is
coated on latex particles and causes agglutination
– The degree of turbidity caused by agglutination is measured optically and is
proportional to the amount of cystatin-c in the sample by a method called
TURBIDIMETRY.
• REFERENCE VALUE-
– Males-0.52-0.98 mg/dl
– Female-0.52-0.90mg/dl
• Normal value decreases until first year of life,then remains stable before increasing
after age of 50 years
• NOTE-
– Cystatin-c can be measured from a random sample of blood from which RBC
and clotting factors have been removed(i.e. serum)
40. TURBIDIMETRY
• Some analytical methods give an insoluble product in finely
divided form so that the particles remain in suspension
• If a beam of light passes through, some of it is scattered-
TYNDALL EFFECT
• Turbidimetry measures the reduction of intensity of the
incident beam and is similar to the study of light absorption
in spectrophotometry
• Turbidimetric measurements are done with usual types of
photometers