Atropine acts as an antagonist to the parasympathetic neurotransmitter acetylcholine at muscarinic receptors. This means that it blocks the effects of the vagus nerve on both the SA node and the AV node, resulting in increased sinus automaticity and improved AV node conduction.

The side effects of atropine are dependent on the dosage and may include dry mouth, nausea and vomiting, blurred vision, urinary retention, and tachyarrhythmias. Elderly patients may also experience acute confusion and hallucinations.

Atropine is recommended for use in cases of sinus, atrial, or nodal bradycardia or AV block when the patient’s hemodynamic condition is unstable due to the bradycardia. According to the ALS bradycardia algorithm, an initial dose of 500 mcg IV is suggested if any adverse features such as shock, syncope, myocardial ischemia, or heart failure are present. If this initial dose is unsuccessful, additional 500 mcg doses can be administered at 3-5 minute intervals, with a maximum dose of 3 mg. It is important to avoid doses exceeding 3 mg as they can paradoxically slow the heart rate.

Asystole during cardiac arrest is typically caused by primary myocardial pathology rather than excessive vagal tone. Therefore, there is no evidence supporting the routine use of atropine in the treatment of asystole or PEA. Consequently, atropine is no longer included in the non-shockable part of the ALS algorithm.

Aside from its use in cardiac conditions, atropine also has other applications. It can be used topically in the eyes as a cycloplegic and mydriatic, to reduce secretions during anesthesia, and in the treatment of organophosphate poisoning.

Bronchiolitis is a short-term infection of the lower respiratory tract that primarily affects infants aged 2 to 6 months. It is commonly caused by a viral infection, with respiratory syncytial virus (RSV) being the most prevalent culprit. RSV infections are most prevalent during the winter months, typically occurring between November and March. In the UK, bronchiolitis is the leading cause of hospitalization among infants.

The typical symptoms of bronchiolitis include fever, difficulty breathing, coughing, poor feeding, irritability, apnoeas (more common in very young infants), and wheezing or fine inspiratory crackles. To confirm the diagnosis, a nasopharyngeal aspirate can be taken for RSV rapid testing. This test is useful in preventing unnecessary further testing and facilitating the isolation of the affected infant.

Most infants with acute bronchiolitis experience a mild, self-limiting illness that does not require hospitalization. Treatment primarily focuses on supportive measures, such as ensuring adequate fluid and nutritional intake and controlling the infant’s temperature. The illness typically lasts for 7 to 10 days.

However, hospital referral and admission are recommended in certain cases, including poor feeding (less than 50% of usual intake over the past 24 hours), lethargy, a history of apnoea, a respiratory rate exceeding 70 breaths per minute, nasal flaring or grunting, severe chest wall recession, cyanosis, oxygen saturations below 90% for children aged 6 weeks and over, and oxygen saturations below 92% for babies under 6 weeks or those with underlying health conditions.

If hospitalization is necessary, treatment involves supportive measures, supplemental oxygen, and nasogastric feeding as needed. There is limited or no evidence supporting the use of antibiotics, antivirals, bronchodilators, corticosteroids, hypertonic saline, or adrenaline nebulizers in the management of bronchiolitis.

The doses of commonly used drugs in paediatric cardiac arrest are summarized in the following table:

Drug: Adrenaline (epinephrine) IV/IO
Dose: 10 mcg/kg

Drug: Adrenaline (epinephrine) ET bolus
Dose: 100 mcg/kg

Drug: Amiodarone IV infusion
Dose: 5 mg/kg over 3 minutes (maximum 300 mg)

Drug: Calcium gluconate 10%
Dose: 0.3-0.5 ml/kg

Drug: Lidocaine IV/IO
Dose: 1 mg/kg (maximum 100 mg)

Drug: Magnesium sulphate IV
Dose: 25-50 mg/kg

Drug: Sodium bicarbonate IV
Dose: 1 ml/kg 8.4%

Sheehan’s syndrome is a condition where the pituitary gland becomes damaged due to insufficient blood flow and shock during and after childbirth, leading to hypopituitarism. The risk of developing this syndrome is higher in pregnancies with conditions that increase the chances of bleeding, such as placenta praevia and multiple pregnancies. Sheehan’s syndrome is quite rare, affecting only 1 in 10,000 pregnancies.

During pregnancy, the anterior pituitary gland undergoes hypertrophy, making it more vulnerable to ischaemia in the later stages. While the posterior pituitary gland is usually unaffected due to its direct arterial supply, there have been rare cases where it is also involved.

The clinical features of Sheehan’s syndrome include the absence or infrequency of menstrual periods, the inability to produce milk and breastfeed (galactorrhoea), decreased libido, fatigue and tiredness, and loss of pubic and axillary hair. Additionally, secondary hypothyroidism and adrenal insufficiency may also occur.

Serum prolactin levels are typically low, measuring less than 5ng/ml. An MRI can be helpful in ruling out other pituitary issues, such as a pituitary tumor.

The management of Sheehan’s syndrome involves hormone replacement therapy. With appropriate treatment, the prognosis for this condition is excellent.

Patients typically initiate dialysis when their glomerular filtration rate (GFR) drops to 10 ml/min. However, if the patient has diabetes, dialysis may be recommended when their GFR reaches 15 ml/min. The GFR is a measure of kidney function and indicates how well the kidneys are able to filter waste products from the blood. Dialysis is a medical procedure that helps perform the function of the kidneys by removing waste and excess fluid from the body.

In this case, the administration of the local anesthetic used for the Bier’s block may have caused the patient’s blood to convert hemoglobin into methemoglobin, resulting in the observed skin color change.

Further Reading:

Bier’s block is a regional intravenous anesthesia technique commonly used for minor surgical procedures of the forearm or for reducing distal radius fractures in the emergency department (ED). It is recommended by NICE as the preferred anesthesia block for adults requiring manipulation of distal forearm fractures in the ED.

Before performing the procedure, a pre-procedure checklist should be completed, including obtaining consent, recording the patient’s weight, ensuring the resuscitative equipment is available, and monitoring the patient’s vital signs throughout the procedure. The air cylinder should be checked if not using an electronic machine, and the cuff should be checked for leaks.

During the procedure, a double cuff tourniquet is placed on the upper arm, and the arm is elevated to exsanguinate the limb. The proximal cuff is inflated to a pressure 100 mmHg above the systolic blood pressure, up to a maximum of 300 mmHg. The time of inflation and pressure should be recorded, and the absence of the radial pulse should be confirmed. 0.5% plain prilocaine is then injected slowly, and the time of injection is recorded. The patient should be warned about the potential cold/hot sensation and mottled appearance of the arm. After injection, the cannula is removed and pressure is applied to the venipuncture site to prevent bleeding. After approximately 10 minutes, the patient should have anesthesia and should not feel pain during manipulation. If anesthesia is successful, the manipulation can be performed, and a plaster can be applied by a second staff member. A check x-ray should be obtained with the arm lowered onto a pillow. The tourniquet should be monitored at all times, and the cuff should be inflated for a minimum of 20 minutes and a maximum of 45 minutes. If rotation of the cuff is required, it should be done after the manipulation and plaster application. After the post-reduction x-ray is satisfactory, the cuff can be deflated while observing the patient and monitors. Limb circulation should be checked prior to discharge, and appropriate follow-up and analgesia should be arranged.

There are several contraindications to performing Bier’s block, including allergy to local anesthetic, hypertension over 200 mm Hg, infection in the limb, lymphedema, methemoglobinemia, morbid obesity, peripheral vascular disease, procedures needed in both arms, Raynaud’s phenomenon, scleroderma, severe hypertension and sickle cell disease.

Acute bacterial prostatitis is a sudden inflammation of the prostate gland, which can be either focal or diffuse and is characterized by the presence of pus. The most common organisms that cause this condition include Escherichia coli, Streptococcus faecalis, Staphylococcus aureus, and Neisseria gonorrhoea. The infection usually reaches the prostate through direct extension from the posterior urethra or urinary bladder, but it can also spread through the blood or lymphatics. In some cases, the infection may originate from the rectum.

According to the National Institute for Health and Care Excellence (NICE), acute prostatitis should be suspected in men who present with a sudden onset of feverish illness, which may be accompanied by rigors, arthralgia, or myalgia. Irritative urinary symptoms like dysuria, frequency, urgency, or acute urinary retention are also common. Perineal or suprapubic pain, as well as penile pain, low back pain, pain during ejaculation, and pain during bowel movements, can occur. A rectal examination may reveal an exquisitely tender prostate. A urine dipstick test showing white blood cells and a urine culture confirming urinary infection are also indicative of acute prostatitis.

The current recommendations by NICE and the British National Formulary (BNF) for the treatment of acute prostatitis involve prescribing an oral antibiotic for a duration of 14 days, taking into consideration local antimicrobial resistance data. The first-line antibiotics recommended are Ciprofloxacin 500 mg twice daily or Ofloxacin 200 mg twice daily. If these are not suitable, Trimethoprim 200 mg twice daily can be used. Second-line options include Levofloxacin 500 mg once daily or Co-trimoxazole 960 mg twice daily, but only when there is bacteriological evidence of sensitivity and valid reasons to prefer this combination over a single antibiotic.

For more information, you can refer to the NICE Clinical Knowledge Summary on acute prostatitis.

The following provides a summary of common causes for different acid-base disorders.

Respiratory alkalosis can be caused by hyperventilation, such as during periods of anxiety. It can also be a result of conditions like pulmonary embolism, CNS disorders (such as stroke or encephalitis), altitude, pregnancy, or the early stages of aspirin overdose.

Respiratory acidosis, on the other hand, is often associated with chronic obstructive pulmonary disease (COPD), life-threatening asthma, pulmonary edema, sedative drug overdose (such as opiates or benzodiazepines), neuromuscular disease, obesity, or other respiratory conditions.

Metabolic alkalosis can occur due to vomiting, potassium depletion (often caused by diuretic usage), Cushing’s syndrome, or Conn’s syndrome.

Metabolic acidosis with a raised anion gap can be caused by lactic acidosis (such as in cases of hypoxemia, shock, sepsis, or infarction), ketoacidosis (such as in diabetes, starvation, or alcohol excess), renal failure, or poisoning (such as in late stages of aspirin overdose, methanol or ethylene glycol ingestion).

Lastly, metabolic acidosis with a normal anion gap can be a result of conditions like diarrhea, ammonium chloride ingestion, or adrenal insufficiency.

For the treatment of women with lower urinary tract infections (UTIs) who are not pregnant, it is recommended to consider either a back-up antibiotic prescription or an immediate antibiotic prescription. This decision should take into account the severity of symptoms and the risk of developing complications, which is higher in individuals with known or suspected abnormalities of the genitourinary tract or weakened immune systems. The evidence for back-up antibiotic prescriptions is limited to non-pregnant women with lower UTIs where immediate antibiotic treatment is not deemed necessary. It is also important to consider previous urine culture and susceptibility results, as well as any history of antibiotic use that may have led to the development of resistant bacteria. Ultimately, the preferences of the woman regarding antibiotic use should be taken into account.

If a urine sample has been sent for culture and susceptibility testing and an antibiotic prescription has been given, it is crucial to review the choice of antibiotic once the microbiological results are available. If the bacteria are found to be resistant and symptoms are not improving, it is recommended to switch to a narrow-spectrum antibiotic whenever possible.

The following antibiotics are recommended for non-pregnant women aged 16 years and older:

First-choice:
– Nitrofurantoin 100 mg modified-release taken orally twice daily for 3 days (if eGFR >45 ml/minute)
– Trimethoprim 200 mg taken orally twice daily for 3 days (if low risk of resistance*)

Second-choice (if there is no improvement in lower UTI symptoms on first-choice treatment for at least 48 hours, or if first-choice treatment is not suitable):
– Nitrofurantoin 100 mg modified-release taken orally twice daily for 3 days (if eGFR >45 ml/minute)
– Pivmecillinam 400 mg initial dose taken orally, followed by 200 mg taken orally three times daily for 3 days
– Fosfomycin 3 g single sachet dose

*The risk of resistance may be lower if the antibiotic has not been used in the past 3 months, previous urine culture suggests susceptibility (although this was not used), and in younger individuals in areas where local epidemiology data indicate low resistance rates. Conversely, the risk of resistance may be higher with recent antibiotic use and in older individuals in residential facilities.

ACE inhibitors should not be used in individuals with HAE because they can enhance the effects of bradykinin. This can lead to drug-induced angioedema, which is a known side effect of ACE inhibitors. In individuals with HAE, ACE inhibitors can trigger attacks of angioedema.

Further Reading:

Angioedema and urticaria are related conditions that involve swelling in different layers of tissue. Angioedema refers to swelling in the deeper layers of tissue, such as the lips and eyelids, while urticaria, also known as hives, refers to swelling in the epidermal skin layers, resulting in raised red areas of skin with itching. These conditions often coexist and may have a common underlying cause.

Angioedema can be classified into allergic and non-allergic types. Allergic angioedema is the most common type and is usually triggered by an allergic reaction, such as to certain medications like penicillins and NSAIDs. Non-allergic angioedema has multiple subtypes and can be caused by factors such as certain medications, including ACE inhibitors, or underlying conditions like hereditary angioedema (HAE) or acquired angioedema.

HAE is an autosomal dominant disease characterized by a deficiency of C1 esterase inhibitor. It typically presents in childhood and can be inherited or acquired as a result of certain disorders like lymphoma or systemic lupus erythematosus. Acquired angioedema may have similar clinical features to HAE but is caused by acquired deficiencies of C1 esterase inhibitor due to autoimmune or lymphoproliferative disorders.

The management of urticaria and allergic angioedema focuses on ensuring the airway remains open and addressing any identifiable triggers. In mild cases without airway compromise, patients may be advised that symptoms will resolve without treatment. Non-sedating antihistamines can be used for up to 6 weeks to relieve symptoms. Severe cases of urticaria may require systemic corticosteroids in addition to antihistamines. In moderate to severe attacks of allergic angioedema, intramuscular epinephrine may be considered.

The management of HAE involves treating the underlying deficiency of C1 esterase inhibitor. This can be done through the administration of C1 esterase inhibitor, bradykinin receptor antagonists, or fresh frozen plasma transfusion, which contains C1 inhibitor.

In summary, angioedema and urticaria are related conditions involving swelling in different layers of tissue. They can coexist and may have a common underlying cause. Management involves addressing triggers, using antihistamines, and in severe cases, systemic corticosteroids or other specific treatments for HAE.

A varicocele is a condition characterized by the presence of varicose veins in the pampiniform plexus of the cord and scrotum. It is more commonly observed in the left testis compared to the right and may be linked to infertility. The primary reason for this association is believed to be the elevated temperature of the testis caused by the presence of varicosities.

Typically, individuals with varicocele experience a dull ache in the testis, which tends to worsen after physical activity or towards the end of the day. The scrotum is often described as feeling like a bag of worms. While the varicocele cannot usually be detected when the patient is lying down, it can often be identified during examination while standing. It is felt as a poorly defined, non-transilluminable mass that is clearly separate from the testis and is located above and behind it. The dilation of the varicocele increases when the Valsalva maneuver is performed, and a cough impulse may also be present.

Conservative treatment is typically recommended for varicocele, with surgery being reserved for severe cases only.

Altitude sickness is usually experienced at altitudes above 2,500 meters (8,000 ft), although some individuals may be affected at lower altitudes. It is important to note that climbers in the UK, where the highest peak is Ben Nevis at 1,345 meters, do not need to worry about altitude sickness.

Further Reading:

High Altitude Illnesses

Altitude & Hypoxia:
– As altitude increases, atmospheric pressure decreases and inspired oxygen pressure falls.
– Hypoxia occurs at altitude due to decreased inspired oxygen.
– At 5500m, inspired oxygen is approximately half that at sea level, and at 8900m, it is less than a third.

Acute Mountain Sickness (AMS):
– AMS is a clinical syndrome caused by hypoxia at altitude.
– Symptoms include headache, anorexia, sleep disturbance, nausea, dizziness, fatigue, malaise, and shortness of breath.
– Symptoms usually occur after 6-12 hours above 2500m.
– Risk factors for AMS include previous AMS, fast ascent, sleeping at altitude, and age <50 years old.
– The Lake Louise AMS score is used to assess the severity of AMS.
– Treatment involves stopping ascent, maintaining hydration, and using medication for symptom relief.
– Medications for moderate to severe symptoms include dexamethasone and acetazolamide.
– Gradual ascent, hydration, and avoiding alcohol can help prevent AMS.

High Altitude Pulmonary Edema (HAPE):
– HAPE is a progression of AMS but can occur without AMS symptoms.
– It is the leading cause of death related to altitude illness.
– Risk factors for HAPE include rate of ascent, intensity of exercise, absolute altitude, and individual susceptibility.
– Symptoms include dyspnea, cough, chest tightness, poor exercise tolerance, cyanosis, low oxygen saturations, tachycardia, tachypnea, crepitations, and orthopnea.
– Management involves immediate descent, supplemental oxygen, keeping warm, and medication such as nifedipine.

High Altitude Cerebral Edema (HACE):
– HACE is thought to result from vasogenic edema and increased vascular pressure.
– It occurs 2-4 days after ascent and is associated with moderate to severe AMS symptoms.
– Symptoms include headache, hallucinations, disorientation, confusion, ataxia, drowsiness, seizures, and manifestations of raised intracranial pressure.
– Immediate descent is crucial for management, and portable hyperbaric therapy may be used if descent is not possible.
– Medication for treatment includes dexamethasone and supplemental oxygen. Acetazolamide is typically used for prophylaxis.

To calculate the overall rate of fluid administration for a patient, we need to consider both the deficit and maintenance requirements. The deficit is determined by the weight of the patient, with a 1kg deficit equaling 1000ml. However, we also need to subtract the 200 ml bolus from the deficit calculation. So, the deficit is 1000 ml – 200 ml = 800 ml.

The deficit calculation is for the next 48 hours, while maintenance is calculated per day. For maintenance, we use the Holliday-Segar formula based on the patient’s weight. For this patient, the formula is as follows:

– 100 ml/kg/day for the first 10 kg of body weight = 10 x 100 = 1000 ml
– 50 ml/kg/day for the next 10 to 20 kg = 50 x 10 = 500 ml
– 20 ml/kg/day for each additional kilogram above 20 kg = 0 (as the patient only weighs 20kg)

So, the total maintenance requirement is 1500 ml per day (over 24 hours), which equals 62 ml/hour.

To determine the overall rate, we add the maintenance requirement (62 ml/hr) to the deficit requirement (17 ml/hr). Therefore, the overall rate of fluid administration for this patient is 79 ml/hr.

Further Reading:

Diabetic ketoacidosis (DKA) is a serious complication of diabetes that occurs due to a lack of insulin in the body. It is most commonly seen in individuals with type 1 diabetes but can also occur in type 2 diabetes. DKA is characterized by hyperglycemia, acidosis, and ketonaemia.

The pathophysiology of DKA involves insulin deficiency, which leads to increased glucose production and decreased glucose uptake by cells. This results in hyperglycemia and osmotic diuresis, leading to dehydration. Insulin deficiency also leads to increased lipolysis and the production of ketone bodies, which are acidic. The body attempts to buffer the pH change through metabolic and respiratory compensation, resulting in metabolic acidosis.

DKA can be precipitated by factors such as infection, physiological stress, non-compliance with insulin therapy, acute medical conditions, and certain medications. The clinical features of DKA include polydipsia, polyuria, signs of dehydration, ketotic breath smell, tachypnea, confusion, headache, nausea, vomiting, lethargy, and abdominal pain.

The diagnosis of DKA is based on the presence of ketonaemia or ketonuria, blood glucose levels above 11 mmol/L or known diabetes mellitus, and a blood pH below 7.3 or bicarbonate levels below 15 mmol/L. Initial investigations include blood gas analysis, urine dipstick for glucose and ketones, blood glucose measurement, and electrolyte levels.

Management of DKA involves fluid replacement, electrolyte correction, insulin therapy, and treatment of any underlying cause. Fluid replacement is typically done with isotonic saline, and potassium may need to be added depending on the patient’s levels. Insulin therapy is initiated with an intravenous infusion, and the rate is adjusted based on blood glucose levels. Monitoring of blood glucose, ketones, bicarbonate, and electrolytes is essential, and the insulin infusion is discontinued once ketones are below 0.3 mmol/L, pH is above 7.3, and bicarbonate is above 18 mmol/L.

Complications of DKA and its treatment include gastric stasis, thromboembolism, electrolyte disturbances, cerebral edema, hypoglycemia, acute respiratory distress syndrome, and acute kidney injury. Prompt medical intervention is crucial in managing DKA to prevent potentially fatal outcomes.

The current gold standard for diagnosing Clostridium difficile colitis is the cytotoxin assay. However, this test has its drawbacks. It can be challenging to perform and results may take up to 48 hours to be available.

The most common laboratory test used to diagnose Clostridium difficile colitis is an enzyme-mediated immunoassay that detects toxins A and B. This test has a specificity of 93-100% and a sensitivity of 63-99%.

Stool culture, although expensive, is not specific for pathogenic strains and therefore cannot be relied upon for a definitive diagnosis of CDAD.

Sigmoidoscopy is not routinely used, but it may be performed in cases where a rapid diagnosis is needed or if the patient has an ileus. Approximately 50% of patients may exhibit the characteristic pseudomembranous appearance, which can be confirmed through a biopsy.

Abdominal X-ray and CT scanning are not typically used, but they can be beneficial in severe cases where complications such as perforation and toxin megacolon are suspected.

It is important to note that a barium enema should not be performed in patients with CDAD as it can be potentially harmful.

Dressler’s syndrome is a form of pericarditis that occurs within 2 to 10 weeks following a heart attack or cardiac surgery. It is distinguished by intense chest pain that is usually alleviated by assuming an upright position. Additionally, individuals may experience a mild fever, a pericardial rub, pulsus paradoxus, and indications of right ventricular failure.

In the UK, the most prevalent cause of hypothyroidism is autoimmune thyroiditis, also known as Hashimoto’s thyroiditis. On a global scale, hypothyroidism is primarily caused by iodine deficiency. However, in areas where iodine levels are sufficient, such as the UK, hypothyroidism and subclinical hypothyroidism are most commonly attributed to autoimmune thyroiditis. This condition can manifest with or without a goitre, known as atrophic thyroiditis.

Further Reading:

The thyroid gland is an endocrine organ located in the anterior neck. It consists of two lobes connected by an isthmus. The gland produces hormones called thyroxine (T4) and triiodothyronine (T3), which regulate energy use, protein synthesis, and the body’s sensitivity to other hormones. The production of T4 and T3 is stimulated by thyroid-stimulating hormone (TSH) secreted by the pituitary gland, which is in turn stimulated by thyrotropin-releasing hormone (TRH) from the hypothalamus.

Thyroid disorders can occur when there is an imbalance in the production or regulation of thyroid hormones. Hypothyroidism is characterized by a deficiency of thyroid hormones, while hyperthyroidism is characterized by an excess. The most common cause of hypothyroidism is autoimmune thyroiditis, also known as Hashimoto’s thyroiditis. It is more common in women and is often associated with goiter. Other causes include subacute thyroiditis, atrophic thyroiditis, and iodine deficiency. On the other hand, the most common cause of hyperthyroidism is Graves’ disease, which is also an autoimmune disorder. Other causes include toxic multinodular goiter and subacute thyroiditis.

The symptoms and signs of thyroid disorders can vary depending on whether the thyroid gland is underactive or overactive. In hypothyroidism, common symptoms include weight gain, lethargy, cold intolerance, and dry skin. In hyperthyroidism, common symptoms include weight loss, restlessness, heat intolerance, and increased sweating. Both hypothyroidism and hyperthyroidism can also affect other systems in the body, such as the cardiovascular, gastrointestinal, and neurological systems.

Complications of thyroid disorders can include dyslipidemia, metabolic syndrome, coronary heart disease, heart failure, subfertility and infertility, impaired special senses, and myxedema coma in severe cases of hypothyroidism. In hyperthyroidism, complications can include Graves’ orbitopathy, compression of the esophagus or trachea by goiter, thyrotoxic periodic paralysis, arrhythmias, osteoporosis, mood disorders, and increased obstetric complications.

Myxedema coma is a rare and life-threatening complication of severe hypothyroidism. It can be triggered by factors such as infection or physiological insult and presents with lethargy, bradycardia, hypothermia, hypotension, hypoventilation, altered mental state, seizures and/or coma.

Epididymo-orchitis refers to the inflammation of the testis and epididymis caused by an infectious source. The most common way of infection is through local extension, often resulting from infections spreading from the urethra or bladder.

In individuals below the age of 35, sexually transmitted pathogens like Chlamydia trachomatis and Neisseria gonorrhoeae are the primary causes. On the other hand, in individuals over the age of 35, non-sexually transmitted infections caused by Gram-negative enteric organisms that lead to urinary tract infections are more common.

Typically, patients with epididymo-orchitis experience sudden onset of unilateral scrotal pain and swelling. The affected testis is tender to touch, and there is usually a noticeable swelling of the epididymis that starts at the lower pole of the testis and spreads towards the upper pole. The testis itself may also be affected, and there may be redness and/or swelling of the scrotum on the affected side. Patients may have a fever and may also have urethral discharge.

It is crucial to consider testicular torsion as the most important differential diagnosis. This should be taken into account for all patients with sudden testicular pain, as the testicle needs to be saved within 6 hours of onset. Torsion is more likely in men under the age of 20, especially if the pain is extremely acute and severe. Typically, torsion presents around four hours after onset. In this case, the patient’s age, longer history of symptoms, and the presence of fever are more indicative of epididymo-orchitis.

The timing of the initial rise, peak, and return to normality of various cardiac enzymes can serve as a helpful guide. Creatine kinase, the main cardiac isoenzyme, typically experiences an initial rise within 4-8 hours, reaches its peak at 18 hours, and returns to normal within 2-3 days. Myoglobin, which lacks specificity due to its association with skeletal muscle damage, shows an initial rise within 1-4 hours, peaks at 6-7 hours, and returns to normal within 24 hours. Troponin I, known for its sensitivity and specificity, exhibits an initial rise within 3-12 hours, reaches its peak at 24 hours, and returns to normal within 3-10 days. HFABP, or heart fatty acid binding protein, experiences an initial rise within 1.5 hours, peaks at 5-10 hours, and returns to normal within 24 hours. Lastly, LDH, predominantly found in cardiac muscle, shows an initial rise at 10 hours, peaks at 24-48 hours, and returns to normal within 14 days.

Type I hypersensitivity reactions are allergic reactions that occur when a person is exposed again to a particular antigen, known as an allergen. These reactions are triggered by IgE and typically happen within 15 to 30 minutes after exposure to the allergen.

A rapid onset of an urticarial rash, which occurs shortly after being exposed to an allergen (such as latex), is highly likely to be caused by a type I hypersensitivity reaction.

Conjunctivitis is the most common reason for red eyes, accounting for about 35% of all eye problems seen in general practice. It occurs when the conjunctiva, the thin layer covering the white part of the eye, becomes inflamed. Conjunctivitis can be caused by an infection or an allergic reaction.

Infective conjunctivitis is inflammation of the conjunctiva caused by a viral, bacterial, or parasitic infection. The most common type of infective conjunctivitis is viral, with adenoviruses being the main culprits. Bacterial conjunctivitis is also common and is usually caused by Streptococcus pneumoniae, Staphylococcus aureus, or Haemophilus influenzae.

The symptoms of infective conjunctivitis include sudden redness of the conjunctiva, discomfort described as a gritty or burning sensation, watering of the eyes, and discharge that may temporarily blurry vision. It can be challenging to differentiate between viral and bacterial conjunctivitis based on symptoms alone.

Here are some key features that can help distinguish between viral and bacterial conjunctivitis:

Features suggestive of viral conjunctivitis:
– Mild to moderate redness of the conjunctiva
– Presence of follicles on the inner surface of the eyelids
– Swelling of the eyelids
– Small, pinpoint bleeding under the conjunctiva
– Pseudomembranes (thin layers of tissue) may form on the inner surface of the eyelids in severe cases, often caused by adenovirus
– Less discharge (usually watery) compared to bacterial conjunctivitis
– Mild to moderate itching
– Symptoms of upper respiratory tract infection and swollen lymph nodes in front of the ears

Features suggestive of bacterial conjunctivitis:
– Purulent or mucopurulent discharge with crusting of the eyelids, which may cause them to stick together upon waking
– Mild or no itching
– Swollen lymph nodes in front of the ears, which are often present in severe bacterial conjunctivitis
– If the discharge is copious and mucopurulent, infection with Neisseria gonorrhoeae should be considered.

By considering these distinguishing features, healthcare professionals can better diagnose and manage cases of conjunctivitis.