Common Kidney Disorders and their Clinical Presentations

Autosomal Dominant Polycystic Kidney Disease (ADPKD)
ADPKD is a progressive disorder characterized by cyst formation and enlargement in the kidney and other organs. Patients may experience pain in the abdomen, flank or back, and hypertension is a common early manifestation. Palpable, bilateral flank masses are present in advanced ADPKD.

Renal Cell Carcinoma (RCC)
RCC is the most common type of kidney cancer in adults. It may remain clinically occult for most of its course, with only 10% of patients presenting with the classic triad of flank pain, haematuria, and unilateral palpable flank mass. RCC presents with hypercalcaemia manifestations in 5% of cases and with varicocele in 2% of men.

Renal Calculi
Renal calculi, or nephrolithiasis, classically present with sudden onset of severe pain originating in the flank and radiating inferiorly and anteriorly. On examination, there is dramatic costovertebral angle tenderness.

Prostatic Carcinoma
Most cases of prostate cancer are identified by screening in asymptomatic men. Symptoms include urinary complaints or retention, back pain, and haematuria. Findings in patients with advanced disease include bony tenderness, lower-extremity oedema or deep venous thrombosis, and an overdistended bladder due to outlet obstruction.

Renal Amyloidosis
Patients with renal amyloidosis typically present with proteinuria and/or hypertension, followed by progressive renal failure. Haematuria is not a feature.

Clinical Presentations of Common Kidney Disorders

Tumour Markers for Common Cancers

Tumour markers are substances produced by cancer cells that can be detected in the blood. They are used to help diagnose and monitor the progression of cancer. Here are the most common tumour markers associated with some of the most prevalent cancers:

Hepatocellular carcinoma: Alpha-fetoprotein (AFP) is the most likely tumour marker associated with this type of liver cancer, which often develops in people with chronic liver diseases.

Breast cancer: Cancer antigen 15-3 (CA 15-3) is the most likely tumour marker associated with breast cancer, which affects both men and women.

Colorectal cancer: Carcinoembryonic antigen (CEA) is the most likely tumour marker associated with colorectal cancer, which can develop from polyps in the colon or rectum.

Pancreatic cancer: CA 19-9 is the most likely tumour marker associated with pancreatic cancer, which is often difficult to detect in its early stages.

Prostate cancer: Prostate-specific antigen (PSA) is the most likely tumour marker associated with prostate cancer, which is the most common cancer in men.

When determining the severity of pancreatitis, the presence of systemic or local complications is the most important factor to consider. Mild acute pancreatitis is characterized by the absence of both organ failure and local complications. Local complications in severe cases may include peripancreatic fluid collections, pancreatic or peripancreatic necrosis, pseudocysts, and walled-off areas of necrosis. The Atlanta classification system categorizes acute pancreatitis as mild, moderate, or severe. Mild cases have no organ failure, local or systemic complications, and typically resolve within a week. Pain level and initial CRP levels are not used to classify severity, but a high white blood cell count may indicate an increased risk of severe pancreatitis. Serum amylase levels and pancreatic calcification on CT scans are also not reliable indicators of severity.

Managing Acute Pancreatitis in a Hospital Setting

Acute pancreatitis is a serious condition that requires management in a hospital setting. The severity of the condition can be stratified based on the presence of organ failure and local complications. Key aspects of care include fluid resuscitation, aggressive early hydration with crystalloids, and adequate pain management with intravenous opioids. Patients should not be made ‘nil-by-mouth’ unless there is a clear reason, and enteral nutrition should be offered within 72 hours of presentation. Antibiotics should not be used prophylactically, but may be indicated in cases of infected pancreatic necrosis. Surgery may be necessary for patients with acute pancreatitis due to gallstones or obstructed biliary systems, and those with infected necrosis may require radiological drainage or surgical necrosectomy.

Medical Conditions that Cause Bilateral Oedema: Inferior Vena Cava Obstruction, Hypoalbuminaemia, Deep Venous Thrombosis, Heart Failure, and Hyponatraemia

Bilateral oedema, or swelling in both legs, can be caused by various medical conditions. One of these is inferior vena cava obstruction, which occurs when a renal mass or thrombus compresses the inferior vena cava, preventing venous drainage of the lower limbs. This obstruction can also cause venous engorgement and dilated veins around the umbilicus. Hypoalbuminaemia, on the other hand, causes a generalised oedema that can be seen in the face, upper and lower limbs, and abdomen. Deep venous thrombosis, which presents with painful swelling and erythema in the affected lower limb, can also cause bilateral symptoms if it occurs in the inferior vena cava. Heart failure, which causes bilateral dependent oedema due to fluid overload, is another possible cause of bilateral oedema. Finally, severe hyponatraemia resulting from fluid overload can cause a generalised symmetrical pattern of oedema that affects the upper limbs as well. Treatment for bilateral oedema depends on the underlying cause.

When a patient with type 2 diabetes and obesity presents with abnormal liver function tests, the most probable diagnosis is non-alcoholic fatty liver disease. To confirm this diagnosis, the patient will need to undergo a liver screen, ultrasound, and liver biopsy. While haemochromatosis should be considered in patients with both abnormal LFTs and diabetes, a normal ferritin level makes this diagnosis less likely.

Non-Alcoholic Fatty Liver Disease: Causes, Features, and Management

Non-alcoholic fatty liver disease (NAFLD) is a prevalent liver disease in developed countries, primarily caused by obesity. It encompasses a range of conditions, from simple steatosis (fat accumulation in the liver) to steatohepatitis (fat with inflammation) and may progress to fibrosis and liver cirrhosis. Insulin resistance is believed to be the primary mechanism leading to steatosis, making NAFLD a hepatic manifestation of metabolic syndrome. Non-alcoholic steatohepatitis (NASH) is a type of liver damage similar to alcoholic hepatitis but occurs in the absence of alcohol abuse. It affects around 3-4% of the general population and may be responsible for some cases of cryptogenic cirrhosis.

NAFLD is usually asymptomatic, but hepatomegaly, increased echogenicity on ultrasound, and elevated ALT levels are common features. The enhanced liver fibrosis (ELF) blood test is recommended by NICE to check for advanced fibrosis in patients with incidental NAFLD. If the ELF blood test is not available, non-invasive tests such as the FIB4 score or NAFLD fibrosis score, in combination with a FibroScan, may be used to assess the severity of fibrosis. Patients with advanced fibrosis should be referred to a liver specialist for further evaluation, which may include a liver biopsy to stage the disease more accurately.

The mainstay of NAFLD treatment is lifestyle changes, particularly weight loss, and monitoring. Research is ongoing into the role of gastric banding and insulin-sensitizing drugs such as metformin and pioglitazone. While there is no evidence to support screening for NAFLD in adults, NICE guidelines recommend the management of incidental NAFLD findings.

Understanding Septic Arthritis in Children

Septic arthritis is a condition that affects children and can lead to permanent joint damage and systemic infection if not treated promptly. It has an incidence of around 4-5 per 100,000 children and is more common in boys, with a M:F ratio of 2:1. The hip, knee, and ankle are the most commonly affected joints. Symptoms of septic arthritis include joint pain, limp, fever, and lethargy. Signs of the condition include a swollen and red joint, with minimal movement possible.

To diagnose septic arthritis, joint aspiration is necessary to culture the affected area. This will show a raised white blood cell count. Inflammatory markers in the blood will also be raised, and blood cultures will be taken. The Kocher criteria are used to diagnose septic arthritis and include a fever of over 38.5 degrees Celsius, non-weight bearing, raised erythrocyte sedimentation rate (ESR), and raised white cell count (WCC).

Understanding septic arthritis in children is crucial for prompt diagnosis and treatment to reduce the risk of permanent joint damage and systemic infection.

Couples are advised to engage in regular sexual intercourse every 2-3 days for a period of 12 months before seeking referral to a specialist. After this time, fertility testing should be conducted, including semen analysis for the male and mid-luteal progesterone level for the female to confirm ovulation. The use of basal body temperature kits is not recommended as they can increase anxiety and have not been proven effective. However, early referral should be considered for females over 35 years of age, those with a history of amenorrhea or pelvic surgery, and those with abnormal genital examinations. Males with a history of genital surgery, STIs, varicocele, or significant systemic illness should also be referred early.

Infertility is a common issue that affects approximately 1 in 7 couples. It is important to note that around 84% of couples who have regular sexual intercourse will conceive within the first year, and 92% within the first two years. The causes of infertility can vary, with male factor accounting for 30%, unexplained causes accounting for 20%, ovulation failure accounting for 20%, tubal damage accounting for 15%, and other causes accounting for the remaining 15%.

When investigating infertility, there are some basic tests that can be done. These include a semen analysis and a serum progesterone test. The serum progesterone test is done 7 days prior to the expected next period, typically on day 21 for a 28-day cycle. The interpretation of the serum progesterone level is as follows: if it is less than 16 nmol/l, it should be repeated and if it remains consistently low, referral to a specialist is necessary. If the level is between 16-30 nmol/l, it should be repeated, and if it is greater than 30 nmol/l, it indicates ovulation.

It is important to counsel patients on lifestyle factors that can impact fertility. This includes taking folic acid, maintaining a healthy BMI between 20-25, and advising regular sexual intercourse every 2 to 3 days. Additionally, patients should be advised to quit smoking and limit alcohol consumption to increase their chances of conceiving.

Common Causes of Bowel Obstruction in Children

Bowel obstruction in children can be caused by various conditions, each with its own distinct features. Here are some of the most common causes:

1. Intussusception: This occurs when one segment of the bowel telescopes into another, leading to obstruction. It is most common in children aged 6-9 months and may be idiopathic or caused by a viral infection. Symptoms include bilious vomiting, distended abdomen, tinkling bowel sounds, and redcurrant jelly stools.

2. Congenital hypertrophic pyloric stenosis: This is a gastric outlet obstruction that typically presents at around 3 weeks of life. It is caused by hypertrophy of the pylorus and leads to non-bilious projectile vomiting and a palpable olive mass in the epigastric region. Treatment involves surgical excision.

3. Duodenal atresia: This is a type of bowel obstruction that only occurs in neonates. It results from failure of recanalization of the small bowel in early fetal life and presents with bilious vomiting, proximal stomach distension, and a double-bubble sign on X-ray. It is associated with Down’s syndrome.

4. Ileus: This is a condition in which the bowel becomes aperistaltic, leading to obstruction. It is common after abdominal surgery, electrolyte disturbances, or infection.

5. Meconium obstruction: This is a type of bowel obstruction that only occurs in newborns. It presents with failure to pass meconium, bilious vomiting, and abdominal distension. Diagnosis can be made prenatally or after birth with an abdominal X-ray showing dilated loops of the small intestine and a soap bubble appearance. Treatment involves radiographic contrast enema or surgery if enemas are unsuccessful.

In conclusion, bowel obstruction in children can have various causes, and prompt diagnosis and treatment are essential to prevent complications.

The patient is experiencing acute kidney injury, which can be categorized into three causes: pre-renal, renal, and post-renal. Pre-renal causes are due to inadequate renal perfusion, such as dehydration, haemorrhage, heart failure, or sepsis. In this case, the kidneys are still able to concentrate urine and retain sodium, resulting in high urine osmolality and low urine sodium. Renal causes are most commonly caused by acute tubular necrosis, which damages tubular cells due to prolonged ischaemia or toxins. In this scenario, the kidneys are unable to concentrate urine or retain sodium, leading to low urine osmolality and high urine sodium. Acute glomerulonephritis and acute interstitial nephritis are rarer causes of renal injury. Post-renal causes are due to obstruction of the urinary tract, which can be identified through hydronephrosis on renal ultrasound.

Distinguishing between Acute Tubular Necrosis and Prerenal Uraemia in Acute Kidney Injury

Acute kidney injury can be caused by various factors, including prerenal uraemia and acute tubular necrosis. It is important to distinguish between the two in order to provide appropriate treatment. Prerenal uraemia occurs when the kidneys hold on to sodium to preserve volume, leading to decreased blood flow to the kidneys. On the other hand, acute tubular necrosis is caused by damage to the kidney tubules, often due to ischemia or toxins.

To differentiate between the two, several factors can be considered. In prerenal uraemia, urine sodium levels are typically less than 20 mmol/L, while in acute tubular necrosis, they are usually greater than 40 mmol/L. Urine osmolality is also a useful indicator, with levels above 500 mOsm/kg suggesting prerenal uraemia and levels below 350 mOsm/kg suggesting acute tubular necrosis.

Fractional sodium excretion and fractional urea excretion are also important measures. In prerenal uraemia, the fractional sodium excretion is typically less than 1%, while in acute tubular necrosis, it is usually greater than 1%. Similarly, the fractional urea excretion is less than 35% in prerenal uraemia and greater than 35% in acute tubular necrosis.

Other factors that can help distinguish between the two include response to fluid challenge, serum urea:creatinine ratio, urine:plasma osmolality, urine:plasma urea ratio, and specific gravity. By considering these factors, healthcare providers can accurately diagnose and treat acute kidney injury.

If a patient with symptomatic stable angina is already on a calcium channel blocker but cannot take a beta-blocker due to a contraindication, the next step in treatment should involve long-acting nitrates, ivabradine, nicorandil, or ranolazine. This scenario involves a 64-year-old man who experiences recurring chest pain during physical activity, which is likely due to poorly controlled stable angina. Although calcium channel blockers and beta-blockers are typically the first-line treatment for stable angina, the patient’s history of asthma makes beta-blockers unsuitable. As the initial treatment has not been effective, the patient should try the next line of therapy. Atenolol, bisoprolol, and diltiazem are not appropriate options for this patient due to their potential risks and lack of effectiveness in this case.

Angina pectoris is a condition that can be managed through various methods, including lifestyle changes, medication, percutaneous coronary intervention, and surgery. In 2011, NICE released guidelines for the management of stable angina. Medication is an important aspect of treatment, and all patients should receive aspirin and a statin unless there are contraindications. Sublingual glyceryl trinitrate can be used to abort angina attacks. The first-line medication should be either a beta-blocker or a calcium channel blocker, depending on the patient’s comorbidities, contraindications, and preferences. If a calcium channel blocker is used as monotherapy, a rate-limiting one such as verapamil or diltiazem should be used. If used in combination with a beta-blocker, a longer-acting dihydropyridine calcium channel blocker should be used. Beta-blockers should not be prescribed concurrently with verapamil due to the risk of complete heart block. If the initial treatment is not effective, medication should be increased to the maximum tolerated dose. If a patient is still symptomatic after monotherapy with a beta-blocker, a calcium channel blocker can be added, and vice versa. If a patient cannot tolerate the addition of a calcium channel blocker or a beta-blocker, other drugs such as long-acting nitrates, ivabradine, nicorandil, or ranolazine can be considered. Nitrate tolerance is a common issue, and patients who take standard-release isosorbide mononitrate should use an asymmetric dosing interval to maintain a daily nitrate-free time of 10-14 hours to minimize the development of nitrate tolerance. This effect is not seen in patients who take once-daily modified-release isosorbide mononitrate. If a patient is taking both a beta-blocker and a calcium-channel blocker, a third drug should only be added while awaiting assessment for PCI or CABG.