Case - Renal Disease

Ultrasound is the most useful method of imaging the kidneys for AKI. Ultrasound uses sound waves to create images of the kidneys and can provide valuable information about the size, shape, and structure of the kidneys. It is a non-invasive procedure that does not involve the use of radiation or contrast agents, making it safe and suitable for patients with renal impairment. Ultrasound can also help identify any abnormalities or blockages in the urinary tract that may be contributing to the AKI. Overall, ultrasound is a reliable and widely available imaging modality for evaluating kidney function in cases of AKI.

The possible causes of AKI include pre-renal acute kidney injury due to dehydration and hypotension, bladder outflow obstruction due to an enlarged prostate, acute interstitial nephritis due to the use of NSAIs like ibuprofen, acute interstitial nephritis due to the use of PPIs like lansoprazole, and multi-system disorders causing intrinsic renal injury. These conditions can all lead to impaired kidney function and the development of AKI.

Crescents on renal biopsy indicate severe glomerular injury. This means that there is significant damage to the glomeruli, which are the filtering units of the kidneys. The presence of crescents suggests that there is inflammation and disruption of the glomerular structure, leading to impaired kidney function. These crescents can be seen in various conditions, including autoimmune diseases like ANCA positive vasculitis and Pulmonary-Renal syndrome. However, they are not specific to these conditions and can also be seen in other forms of glomerular injury. Therefore, the presence of crescents on renal biopsy is an important finding that indicates severe damage to the kidneys.

Urinalysis - dipstick for blood and protein and urine microscopy are the most useful tests to clarify the cause of AKI. The dipstick for blood and protein can help identify any abnormalities in the urine, such as the presence of blood or protein, which can indicate underlying kidney damage. Urine microscopy involves examining a urine sample under a microscope to look for the presence of red and white blood cells, casts, crystals, or bacteria, which can further help in determining the cause of AKI. These tests provide valuable information about the kidney function and can aid in diagnosing the underlying condition causing AKI.

Patients with Rapidly Progressive Glomerulonephritis (RPGN) can rapidly become unwell with multi-system symptoms, such as kidney failure, lung involvement, and other organ dysfunction. Additionally, all c ANCA positive patients are at risk of developing pulmonary involvement. Rapid aggressive immunosuppression is necessary in order to salvage damaged nephrons and restore useful renal function. Therefore, speed is crucial in dealing with RPGN to prevent further complications and improve patient outcomes.

Microscopic vasculitis can present with various symptoms, including episcleritis (inflammation of the outermost layer of the sclera), skin rashes, joint pains, nosebleeds, gastrointestinal bleeds, acute kidney injury (AKI), chronic kidney disease (CKD), pulmonary hemorrhage, mononeuritis multiplex (inflammation of multiple nerves), and seizures due to intracerebral hemorrhage. These symptoms can occur due to inflammation and damage to the blood vessels in different organs and tissues of the body.

The options listed are all potential treatments for microscopic vasculitis. Steroids are commonly used to reduce inflammation and suppress the immune system. Cortimoxazole is an antibiotic that can be used to treat infections associated with vasculitis. Cyclophosphamide is a chemotherapy drug that can suppress the immune system and reduce inflammation. MMF, or mycophenolate mofetil, is an immunosuppressive medication that can be used to treat vasculitis. Plasmapheresis is a procedure where the liquid part of the blood, called plasma, is separated from the blood cells. This can help remove harmful antibodies and other substances from the blood. Rituximab is a medication that targets certain cells of the immune system and can be used to treat vasculitis.

Positive C ANCA (antineutrophil cytoplasmic antibody) is a marker of microscopic vasculitis, specifically associated with Wegener's Granulomatosis. It suggests the presence of intrinsic renal disease.

In Acute Kidney Injury (AKI), oliguria, which is a decreased urine output, is a common symptom. Biochemically, there is an increase in plasma urea and creatinine levels, indicating impaired kidney function. AKI is more common in the elderly population. Additionally, AKI is most commonly caused by pre-renal factors, such as decreased blood flow to the kidneys, rather than intrinsic or post-renal causes.

Pre Renal AKI is a type of acute kidney injury that is caused by decreased blood flow to the kidneys, leading to impaired kidney function. It can be a secondary effect of peritonitis, sepsis, anaphylaxis, heart failure, and adverse drug reactions such as NSAIDs and ACE inhibitors. This condition is not irreversible, as it can be resolved by addressing the underlying cause and restoring proper blood flow to the kidneys.

The more likely causes of shortness of breath in a young patient who has been hospitalized with AKI associated with dyspnoea are pulmonary oedema, hospital-acquired pneumonia, and pulmonary haemorrhage. Pulmonary oedema refers to the accumulation of fluid in the lungs, which can cause difficulty in breathing. Hospital-acquired pneumonia is a lung infection that develops during a hospital stay and can lead to respiratory symptoms. Pulmonary haemorrhage refers to bleeding in the lungs, which can also result in shortness of breath.

RBC Casts always indicate renal disease and RBC Casts indicate, most commonly, glomerulonephritis because the presence of red blood cell casts in urine microscopy is a strong indication of renal disease. Glomerulonephritis is the most common cause of RBC casts. White Cell Casts can be seen in acute pyelonephritis, which is an infection of the kidneys. Some casts may be normal, as not all casts are pathological. Coarsely granulated casts indicate glomerular/tubular disease and are associated with pathological proteinuria.

Haematuria, proteinuria, and RBC casts are all indicators of glomerular damage. P-ANCA is present in Microscopic Polyangitis. Anti-glomerular basement membrane antibody disease and Goodpastures are synonymous. Glomerular AKI is associated with edema and hypertension. Tubulo-interstitium injury is usually normal on urinalysis. It can be caused by ischemia. Radiocontrast and rhabdomyolysis are major causes of tubulo-interstitium damage. Diuretics and NSAIDs can produce acute allergic interstitial nephritis.

Nephritic syndrome is characterized by inflammation of the glomeruli in the kidneys. This leads to leakage of protein in the urine (proteinurea), low levels of albumin in the blood (hypoalbuminaemia), and accumulation of fluid in the body (oedema). Haematuria, the presence of blood in the urine, is also associated with nephritic syndrome. It can cause progressive renal disease, leading to kidney damage. Other possible causes of nephritic syndrome include IgA nephropathy, lupus, and hypertension. C3 deposition, a marker of complement activation, is also associated with nephritic syndrome.

Nephrotic syndrome is characterized by a group of symptoms including proteinuria (presence of excess protein in the urine), hypoalbuminemia (low levels of albumin in the blood), edema (swelling due to fluid retention), hyperlipidemia (high levels of lipids in the blood), prothrombotic state (increased risk of blood clots), can cause progressive renal disease, IgG nephropathy, diabetes, lupus, NSAIDs, and C3 deposition. These are all associated with the pathophysiology and clinical presentation of nephrotic syndrome.