Nephrology

Nephrology

General Nephrology deals with the treatment and management of Nephrotic syndrome, acute nephritic syndrome, acute renal failure and chronic renal failure. Being a tertiary care center, all types of acute renal failure are encountered. Diabetic Nephropathy is the most commonly encountered chronic kidney disease. Given below are the descriptions of the conditions treated:

·         Nephrotic Syndrome:

Is a condition where a patient develops swelling of the legs and face and is found to have severe protein excretion in the urine. Kidney biopsy is required in adults to know the cause of this condition

·         Acute Nephritic Syndrome:

Is a condition commonly affecting children. Usually in this condition, following a sore throat or a skin infection, the child develops red urine (due to blood in the urine), swelling of the face and legs, and increase in blood pressure. It is usually a self-limiting process that clears up by itself in a few days to a few weeks time

·         Acute Renal Failure:

Is a potentially reversible cause of kidney failure. Common causes are dehydration due to loose motion and vomiting , infections, certain drugs, snakebite and blockage to the passage of urine

·         Chronic Renal Failure:

Is irreversible kidney failure. The causes for chronic renal failure are diabetes mellitus (the most common cause), hypertension, long-term usage of painkillers, certain genetic diseases, recurrent urinary tract infections (especially in children), and certain other primary kidney diseases

Dialysis

When end-stage renal failure occurs (that is, when the kidney function is irreversibly reduced to below 15% of normal), there are two treatment options: dialysis or a kidney transplant (also known as a renal transplant).

There are two types of dialysis: haemodialysis and peritoneal dialysis. This page deals with haemodialysis.

The word ‘haemo’ refers to blood. Haemodialysis is a process that balances blood chemistry and filters wastes and fluid from the blood.

For haemodialysis, two needles are inserted into the patient’s arm. One needle withdraws the blood and the other returns the filtered blood to the patient’s body.

The blood, which is withdrawn by the first needle, travels outside the body through tubing and the dialysis machine then pumps this blood through a filter called a dialyser, which is attached to the dialysis machine. The dialyser cleans the blood and it is returned to the patient’s body through the other needle.

The dialyser is also called an artificial kidney because it is an artificial replacement for the patient’s damaged kidneys. During the process of haemodialysis, the haemodialysis machine circulates the dialysate (fluid with chemicals that helps to remove wastes from the body) to the artificial kidney. Haemodialysis is typically performed at a dialysis centre.

Peritoneal Dialysis

When end-stage renal failure occurs (that is, when the kidney function is irreversibly reduced to below 15% of normal), there are two treatment options: dialysis or a kidney transplant (also known as a renal transplant)

There are two types of dialysis: haemodialysis and peritoneal dialysis. This page deals with peritoneal dialysis

In peritoneal dialysis, the patient’s peritoneum (membrane present inside the abdomen) is used for the purpose of dialysis. Peritoneal dialysis occurs within the patient’s body itself

For peritoneal dialysis, a tube called a catheter is surgically placed through the wall of the patient’s abdomen as a permanent access for peritoneal dialysis. The catheter is usually placed about an inch below and to the side of the navel. About 2-4 inches of the catheter extends out of the body

Through the catheter, the peritoneum is filled with the peritoneal dialysate (fluid with chemicals that helps to remove wastes from the body). The dialysate absorbs the excess water and the waste products. The dialysate remains in the peritoneum for a certain period of time. This is known as dwell time. After this period, the solution, along with the wastes, is drained from the abdomen into a sterile collection bag

Types of Peritoneal Dialysis

Peritoneal dialysis is of the following types:

  • Intermittent Peritoneal Dialysis (IPD):Intermittent peritoneal dialysis is offered to patients on a temporary basis when their blood pressure is low or in children with acute renal failure to tide over a crisis. It is performed for a short period of 24-48 hours
  • Continuous Ambulatory Peritoneal Dialysis (CAPD):In CAPD, the patient’s peritoneum is manually filled by hand with the dialysate and there are no dry periods
  • Automated Peritoneal Dialysis (APD):APD is performed through a cycler machine. It is performed during the night when the patient is asleep
  • Continuous Cyclic Peritoneal Dialysis (CCPD):In CCPD, the patient’s peritoneum is filled with the dialysate by a machine at night and the exchanges are carried out throughout the night. As the patient is not attached to the machine during the day, it enables the patient to be more mobile during the day
  • Daytime Ambulatory Peritoneal Dialysis (DAPD):In DAPD, the patient’s peritoneum is filled with the dialysate during he day and it is dry at night
  • Night-Time Intermittent Peritoneal Dialysis (NIPD):In NIPD, the patient’s peritoneal cavity is filled with the dialysate manually or with a cycler at night and it is dry during the day

CRRT

A few patients who are admitted to the ICU and are very sick with multi-organ damage, including renal failure and with low blood pressure, require CRRT (Continuous Renal Replacement Therapy) – a form of specialized dialysis. A separate dialysis machine is dedicated for this procedure. Patients are monitored around the clock during the procedure, which is carried out continuously for a period of 24 to 48 hours.

Plasmapheresis

Plasmapheresis is a specialized procedure that is performed in the ICU for certain patients who are very sick with some specific kidney diseases. In this procedure large quantities of plasma is removed from a patient and replaced with fresh frozen plasma, albumin or saline.

A vascular access in the form of internal jugular catheter / femoral vein catheter / AV fistula / AV graft is required. A plasmafilter is used for the procedure. Haemodialysis machine with the blood pump and blood lines are used. Replacement fluid is infused into the blood line. Anticoagulation is used appropriately.

Some of the conditions requiring plasmapheresis are anti GBM disease, Hemolytic Uraemic Syndrome / Thrombotic thrombocytopenic purpura, cryoglobulinemia, some vasculitic processes, recurrent FSGS in renal transplant, sensitized patients waiting for renal transplant.

Renal (Kidney) Biopsy

Renal biopsy is a diagnostic procedure in which a small piece of renal tissue (tissue from the kidneys) is obtained to know the cause of renal failure, to know the cause of proteinuria and to know the severity in some renal diseases like lupus nephritis.

Ultrasound-guided renal biopsy can be that of the native kidneys or that of the transplant kidney is routinely performed under local anesthesia in adults but children need general anesthesia. Bedside renal biopsies are performed for sick patients in the ICU and in the ward.

Patient needs to get admitted on the morning of the procedure & need to be under complete bed rest for a day after the procedure. He can resume his normal activities couple of days after the procedure.

Some investigations like coagulation parameters need to be checked prior to renal biopsy. Complications like blood in the urine can occur in about 5% of patients. Rarely the bleeding can be severe to warrant another procedure to stop the bleeding.

On rare occasions a repeat renal biopsy may be required if the original biopsy is unsuccessful.

Renal (Kidney) Transplant