Understanding Acute Interstitial Nephritis and its Causes

Acute interstitial nephritis is a condition that results in acute kidney injury. The most common cause of this condition is a drug hypersensitivity reaction, accounting for 40-60% of cases. However, drugs used for Parkinson’s disease are not known to cause nephritis.

Wilson’s disease, on the other hand, is a condition characterized by abnormal copper metabolism. It typically presents as liver disease in children and adolescents, and as neuropsychiatric illness in young adults, which may include Parkinsonian features. Although haematuria has been reported in Wilson’s disease, gross haematuria is uncommon in urinary tract infection.

L-Dopa is the primary treatment for Parkinson’s disease, and it can cause reddish discolouration of urine and other body fluids. In contrast, bromocriptine doesn’t have this side effect. While the BNF reports that the side effect of bromocriptine is uncommon, it would still be wise to test the urine for blood.

In the UK, breast cancer screening is currently offered to women between the ages of 50 and 70 every three years. However, there are plans to expand this service to include women aged 47 to 73 by the end of 2016. Additionally, women between the ages of 40 and 50 who are at a high risk of developing breast cancer may be offered screening every two years.

Breast Cancer Screening and Familial Risk Factors

Breast cancer screening is offered to women aged 50-70 years through the NHS Breast Screening Programme, with mammograms offered every three years. While the effectiveness of breast screening is debated, it is estimated that the programme saves around 1,400 lives annually. Women over 70 years may still have mammograms but are encouraged to make their own appointments.

For those with familial risk factors, NICE guidelines recommend referral to a breast clinic for further assessment. Those with one first-degree or second-degree relative diagnosed with breast cancer do not need referral unless certain factors are present in the family history, such as early age of diagnosis, bilateral breast cancer, male breast cancer, ovarian cancer, Jewish ancestry, or complicated patterns of multiple cancers at a young age. Women with an increased risk of breast cancer due to family history may be offered screening from a younger age.

For patients with chronic kidney disease, hypertension, and a urinary albumin:creatinine ratio (ACR) of 70 or more, it is recommended to aim for a lower blood pressure target of <130/80 mmHg. This approach can provide advantages such as reducing the risk of cardiovascular complications and slowing the progression of the disease. However, if the patient’s ACR is less than 70 mg/mmol, the blood pressure target can be slightly higher at <140/90 mmHg. For individuals under 80 years old, the recommended target for home blood pressure readings is <135/85 mmHg. Chronic kidney disease (CKD) patients often require more than two drugs to manage hypertension. The first-line treatment is ACE inhibitors, which are especially effective in proteinuric renal disease like diabetic nephropathy. However, these drugs can reduce filtration pressure, leading to a slight decrease in glomerular filtration pressure (GFR) and an increase in creatinine. NICE guidelines state that a decrease in eGFR of up to 25% or a rise in creatinine of up to 30% is acceptable, but any increase should prompt careful monitoring and exclusion of other causes. If the rise is greater than this, it may indicate underlying renovascular disease. Furosemide is a useful Antihypertensive drug for CKD patients, particularly when the GFR falls below 45 ml/min*. It also helps to lower serum potassium levels. However, high doses are usually required, and if the patient is at risk of dehydration (e.g. due to gastroenteritis), the drug should be temporarily stopped. The NKF K/DOQI guidelines suggest a lower cut-off of less than 30 ml/min.

Diagnosing Nephrotic Syndrome: The Importance of Proteinuria and Renal Biopsy

Nephrotic syndrome is characterized by proteinuria (>3g/24 hours), hypoalbuminaemia (<30g/l), and oedema. To quantify proteinuria, a urine ACR or PCR or 24-hour urine collection is required. However, heavy proteinuria on urine dipstick is sufficient to confirm the need for a renal biopsy. Before a renal biopsy, a renal ultrasound is necessary to ensure the presence of two kidneys and confirm kidney size and position. Autoantibodies aid in diagnosis, but the initial confirmatory investigation is the dipstick. In children and young adults, minimal change glomerulonephritis is the most likely renal biopsy finding, which may be steroid responsive and has a good prognosis.

CKD is diagnosed when there is evidence of kidney damage or a decrease in kidney function for at least three months. This can be determined by a persistent eGFR of less than 60 mL/min/1.73 m2 or a change in GFR category or sustained decrease in eGFR of 15 mL/min/1.73 m2 or more within 12 months. Additionally, a urinary albumin:creatinine ratio (ACR) of 70 mg/mmol or more, unless proteinuria is known to be associated with diabetes mellitus and is managed appropriately, or a urinary ACR of 30 mg/mmol or more together with persistent haematuria, after exclusion of a urinary tract infection (UTI), can also indicate CKD. Other indications include hypertension that remains uncontrolled despite the use of at least four antihypertensive drugs at therapeutic doses, a suspected or confirmed rare or genetic cause of CKD, such as polycystic kidney disease, suspected renal artery stenosis, or a suspected complication of CKD.

Chronic kidney disease (CKD) is a condition where the kidneys are not functioning properly. To estimate renal function, serum creatinine levels are often used, but this may not be accurate due to differences in muscle. Therefore, formulas such as the Modification of Diet in Renal Disease (MDRD) equation are used to estimate the glomerular filtration rate (eGFR). The MDRD equation takes into account serum creatinine, age, gender, and ethnicity. However, factors such as pregnancy, muscle mass, and recent red meat consumption may affect the accuracy of the result.

CKD can be classified based on the eGFR. Stage 1 CKD is when the eGFR is greater than 90 ml/min, but there are signs of kidney damage on other tests. If all kidney tests are normal, there is no CKD. Stage 2 CKD is when the eGFR is between 60-90 ml/min with some sign of kidney damage. Stage 3a and 3b CKD are when the eGFR is between 45-59 ml/min and 30-44 ml/min, respectively, indicating a moderate reduction in kidney function. Stage 4 CKD is when the eGFR is between 15-29 ml/min, indicating a severe reduction in kidney function. Stage 5 CKD is when the eGFR is less than 15 ml/min, indicating established kidney failure, and dialysis or a kidney transplant may be necessary. It is important to note that normal U&Es and no proteinuria are required for a diagnosis of CKD.

Causes of Haematospermia in a Young Adult

Haematospermia, the presence of blood in semen, can be a distressing symptom for men. In those under 40 years of age, infections are the most common cause, with sexually transmitted infections (STIs) such as chlamydia being a likely culprit, especially in the absence of urinary symptoms. Haemophilia A, a genetic disorder that affects blood clotting, is unlikely to present with haematospermia as the first symptom, especially in a young adult. Malignant hypertension, a rare and severe form of high blood pressure, can cause end-organ damage but is an unusual cause of haematospermia. Prostate cancer, which is more common in older men, can also cause haematospermia, but is usually associated with urinary symptoms and erectile dysfunction. Prostatitis, an inflammation of the prostate gland, can cause haematospermia and other symptoms such as pain and fever, but is less common than UTIs or STIs. A thorough medical history, physical examination, and appropriate investigations can help identify the underlying cause of haematospermia and guide treatment.

Understanding Anaemia in Chronic Kidney Disease

Anaemia is a common complication in patients with chronic kidney disease, with a prevalence of about 12%. As the estimated glomerular filtration rate (eGFR) falls, the prevalence of anaemia increases. Patients should be investigated if their haemoglobin falls to 110g/L or less or if symptoms of anaemia develop.

The typical normochromic normocytic anaemia of chronic kidney disease mainly develops from decreased renal synthesis of erythropoietin. Anaemia becomes more severe as the glomerular filtration rate decreases. Iron deficiency is also common and may be due to poor dietary intake or occult bleeding. Other factors contributing to anaemia include the presence of uraemic inhibitors, a reduced half-life of circulating blood cells, or deficiency of folate or vitamin B12.

Although supplements of vitamin C have been used as adjuvant therapy in the anaemia of chronic kidney disease, NICE recommends that they should not be prescribed for this purpose as evidence suggests no benefit. It is important to monitor and manage anaemia in patients with chronic kidney disease to improve their quality of life and reduce the risk of complications.

Factors Affecting Prostate-Specific Antigen Blood Test

The prostate-specific antigen (PSA) blood test is a common diagnostic tool used to detect prostate cancer. However, the test results can be influenced by various factors, including benign prostatic hypertrophy, prostatitis, urinary retention, urinary tract infection, old age, urethral or rectal instrumentation/examination, recent vigorous exercise, and recent ejaculation.

It is important to note that the PSA test should be deferred for at least a month in individuals with a proven urinary tract infection. Additionally, if a man has ejaculated or exercised vigorously in the previous 48 hours, the test should also be deferred. While some sources suggest delaying PSA testing for at least a week after a digital rectal examination, data suggest that rectal examination has minimal effect on PSA levels.

In summary, it is crucial to consider these factors when interpreting PSA test results to ensure accurate diagnosis and treatment.

Managing Renovascular Disease: Treatment Options and Lifestyle Modifications

Renovascular disease, caused by atherosclerosis or fibromuscular dysplasia, can lead to resistant hypertension and ischaemic nephropathy, particularly in older individuals with diffuse atherosclerosis. Lifestyle modifications, such as smoking cessation, diabetes control, statins, aspirin, and adequate antihypertensive therapy, are crucial in reducing vascular risk. However, some patients may not tolerate ACE inhibitors or angiotensin II receptor antagonists, which are commonly used to preserve GFR.

Oral anticoagulants are not recommended as a first-line measure. Instead, medication for blood pressure control, with or without intervention, is necessary to prevent or limit the progression of chronic kidney disease and alleviate other symptoms, such as refractory pulmonary oedema and angina. Percutaneous renal artery balloon angioplasty may be considered in patients with difficult-to-control hypertension or rapidly declining kidney function. Renal artery stenting is generally the first-line intervention for flash pulmonary oedema and severe hypertension. Surgical reconstruction of the renal arteries is reserved for patients with concomitant vascular disease, such as abdominal aortic aneurysm.

In summary, managing renovascular disease requires a combination of lifestyle modifications and appropriate medical interventions to reduce vascular risk and alleviate symptoms.

Prostate Cancer and Prostatism: Symptoms and Diagnosis

Patients with prostatism who experience bony pain should be evaluated for prostate cancer, as it often metastasizes to bone. A digital rectal examination should be performed after taking blood for PSA, as the prostate will typically feel hard and irregular in cases of prostate cancer. While chronic urinary retention and urinary infection may be present, investigations should focus on identifying the underlying cause rather than providing symptomatic treatment with an α-blocker. Without a confirmed diagnosis of benign prostatic hyperplasia, finasteride should not be prescribed.