Anticholinergic drugs work by blocking the effects of acetylcholine, a neurotransmitter, in both the central and peripheral nervous systems. These drugs are commonly used in clinical practice and include antihistamines, typical and atypical antipsychotics, anticonvulsants, antidepressants, antispasmodics, antiemetics, antiparkinsonian agents, antimuscarinics, and certain plants. When someone ingests an anticholinergic drug, they may experience a toxidrome, which is characterized by an agitated delirium and various signs of acetylcholine receptor blockade in the central and peripheral systems.

The central effects of anticholinergic drugs result in an agitated delirium, which is marked by fluctuating mental status, confusion, restlessness, visual hallucinations, picking at objects in the air, mumbling, slurred speech, disruptive behavior, tremor, myoclonus, and in rare cases, coma or seizures. On the other hand, the peripheral effects can vary and may include dilated pupils, sinus tachycardia, dry mouth, hot and flushed skin, increased body temperature, urinary retention, and ileus.

Digoxin-specific antibody (DigiFab) is an antidote used to counteract digoxin overdose. It is a purified and sterile preparation of digoxin-immune ovine Fab immunoglobulin fragments. These fragments are derived from healthy sheep that have been immunized with a digoxin derivative called digoxin-dicarboxymethoxylamine (DDMA). DDMA is a digoxin analogue that contains the essential cyclopentanoperhydrophenanthrene: lactone ring moiety coupled to keyhole limpet hemocyanin (KLH).

DigiFab has a higher affinity for digoxin compared to the affinity of digoxin for its sodium pump receptor, which is believed to be the receptor responsible for its therapeutic and toxic effects. When administered to a patient who has overdosed on digoxin, DigiFab binds to digoxin molecules, reducing the levels of free digoxin in the body. This shift in equilibrium away from binding to the receptors helps to reduce the cardiotoxic effects of digoxin. The Fab-digoxin complexes are then eliminated from the body through the kidney and reticuloendothelial system.

The indications for using DigiFab in cases of acute and chronic digoxin toxicity are summarized below:

Acute digoxin toxicity:
– Cardiac arrest
– Life-threatening arrhythmia
– Potassium level >5 mmol/l
– Ingestion of >10 mg of digoxin (in adults)
– Ingestion of >4 mg of digoxin (in children)
– Digoxin level >12 ng/ml

Chronic digoxin toxicity:
– Cardiac arrest
– Life-threatening arrhythmia
– Significant gastrointestinal symptoms
– Symptoms of digoxin toxicity in the presence of renal failure

The term Apparent Life-Threatening Event (ALTE) has traditionally been used to describe a specific type of event. However, in 2016, the American Academy of Paediatrics (AAP) recommended replacing this term with a new one called Brief Resolved Unexplained Event (BRUE).

An ALTE is defined as an episode that is frightening to the observer and is characterized by a combination of symptoms such as apnoea (central or occasionally obstructive), color change (usually cyanotic or pallid but occasionally erythematous or plethoric), significant change in muscle tone (usually marked limpness), choking, or gagging. In some cases, the observer may even fear that the infant has died.

On the other hand, BRUE has stricter criteria and is only applicable to episodes that occur in infants under 12 months old. A BRUE is considered brief, typically lasting 2-30 seconds but no longer than 1 minute. It must also have resolved, meaning the infant has returned to their baseline state. Additionally, it should not be explained by any identifiable medical condition and must be characterized by at least one of the following: cyanosis or pallor, absent, decreased, or irregular breathing, marked change in muscle tone (hyper- or hypotonia), or altered level of responsiveness.

To diagnose a BRUE, a full history and physical examination of the infant must be conducted, and if no explanation for the event is found, it can be classified as a BRUE. Once a BRUE is diagnosed, it can be risk-stratified to guide further management.

A BRUE is considered low risk if the infant has fully recovered, there are no concerning history or physical examination findings, and the following criteria are met: the infant is over 60 days old, born after 32 weeks gestation with a corrected gestational age over 45 weeks, no CPR was performed by a trained healthcare professional, and this was the first event that lasted less than 1 minute.

Low-risk infants can be safely discharged with early outpatient follow-up within 24 hours. However, it is important to involve the parents/caregivers in the decision-making process. They should be informed that a low-risk BRUE is unlikely to indicate a severe underlying disorder and that the event is unlikely to happen again.

Before discharge, it may be advisable to perform an ECG, observe the infant for a brief period, and conduct a pertussis swab

The primary way hepatitis A is transmitted is through the ingestion of fecal matter containing the virus. On the other hand, all the other organisms mentioned in this question are typically transmitted through sexual contact.

According to the latest NICE guidance, it is recommended that women aged 55 and over with unexplained symptoms of vaginal discharge should undergo a direct access ultrasound scan to assess for endometrial cancer. This recommendation applies to women who are experiencing these symptoms for the first time or who have thrombocytosis, haematuria (blood in the urine), visible haematuria, low haemoglobin levels, or high blood glucose levels. For more information, please refer to the NICE referral guidelines on the recognition and referral of suspected cancer.

This patient has presented with an Addisonian crisis, which is a rare but potentially catastrophic condition if not diagnosed promptly. The most likely underlying rheumatological diagnosis in this case is polymyalgia rheumatica, and it is likely that the GP started the patient on prednisolone medication.

Addison’s disease occurs when the adrenal glands underproduce steroid hormones, affecting the production of glucocorticoids, mineralocorticoids, and sex steroids. The main causes of Addison’s disease include autoimmune adrenalitis (accounting for 80% of cases), bilateral adrenalectomy, Waterhouse-Friderichsen syndrome (hemorrhage into the adrenal glands), and tuberculosis.

An Addisonian crisis is most commonly triggered by the deliberate or accidental withdrawal of steroid therapy in patients with Addison’s disease. Other factors that can precipitate a crisis include infection, trauma, myocardial infarction, cerebral infarction, asthma, hypothermia, and alcohol abuse.

The clinical features of Addison’s disease include weakness, lethargy, hypotension (especially orthostatic hypotension), nausea, vomiting, weight loss, reduced axillary and pubic hair, depression, and hyperpigmentation (particularly in palmar creases, buccal mucosa, and exposed areas). In an Addisonian crisis, the main features are usually hypoglycemia and shock, characterized by tachycardia, peripheral vasoconstriction, hypotension, altered consciousness, and coma.

Biochemically, Addison’s disease is characterized by increased ACTH levels (as a compensatory response to stimulate the adrenal glands), elevated serum renin levels, hyponatremia, hyperkalemia, hypercalcemia, hypoglycemia, and metabolic acidosis. Diagnostic investigations may include the Synacthen test, plasma ACTH level, plasma renin level, and adrenocortical antibodies.

Management of Addison’s disease should be overseen by an Endocrinologist. Typically, patients require hydrocortisone, fludrocortisone, and dehydroepiandrosterone. Some patients may also need thyroxine if there is hypothalamic-pituitary disease present. Treatment is lifelong, and patients should carry a steroid card and a MedicAlert bracelet, being aware of the possibility of an Addisonian crisis.

The management of anaphylaxis involves several important steps. First and foremost, it is crucial to ensure proper airway management. Additionally, early administration of adrenaline is essential, preferably in the anterolateral aspect of the middle third of the thigh. Aggressive fluid resuscitation is also necessary. In severe cases, intubation may be required. However, it is important to note that the administration of chlorpheniramine and hydrocortisone should only be considered after early resuscitation has taken place.

Adrenaline is the most vital medication for treating anaphylactic reactions. It acts as an alpha-adrenergic receptor agonist, which helps reverse peripheral vasodilatation and reduce oedema. Furthermore, its beta-adrenergic effects aid in dilating the bronchial airways, increasing the force of myocardial contraction, and suppressing histamine and leukotriene release. Administering adrenaline as the first drug is crucial, and the intramuscular (IM) route is generally the most effective for most individuals.

The recommended doses of IM adrenaline for different age groups during anaphylaxis are as follows:

– Children under 6 years: 150 mcg (0.15 mL of 1:1000)
– Children aged 6-12 years: 300 mcg (0.3 mL of 1:1000)
– Children older than 12 years: 500 mcg (0.5 mL of 1:1000)
– Adults: 500 mcg (0.5 mL of 1:1000)

BPPV is a condition where patients experience vertigo and nystagmus. The Dix-Hallpike test is used to diagnose BPPV, and it involves observing torsional (rotary) and vertical nystagmus. Unlike vertigo caused by vestibular neuritis and labyrinthitis, BPPV is not associated with prodromal viral illness, hearing loss, or tinnitus. The episodes of vertigo and dizziness in BPPV usually last for 10-20 seconds, with episodes lasting over 1 minute being uncommon.

Further Reading:

Benign paroxysmal positional vertigo (BPPV) is a common cause of vertigo, characterized by sudden dizziness and vertigo triggered by changes in head position. It typically affects individuals over the age of 55 and is less common in younger patients. BPPV is caused by dysfunction in the inner ear, specifically the detachment of otoliths (calcium carbonate particles) from the utricular otolithic membrane. These loose otoliths move through the semicircular canals, triggering a sensation of movement and resulting in conflicting sensory inputs that cause vertigo.

The majority of BPPV cases involve otoliths in the posterior semicircular canal, followed by the inferior semicircular canal. BPPV in the anterior semicircular canals is rare. Clinical features of BPPV include vertigo triggered by head position changes, such as rolling over in bed or looking upwards, accompanied by nausea. Episodes of vertigo typically last 10-20 seconds and can be diagnosed through positional nystagmus, which is a specific eye movement, observed during diagnostic maneuvers like the Dix-Hallpike maneuver.

Hearing loss and tinnitus are not associated with BPPV. The prognosis for BPPV is generally good, with spontaneous resolution occurring within a few weeks to months. Symptomatic relief can be achieved through the Epley maneuver, which is successful in around 80% of cases, or patient home exercises like the Brandt-Daroff exercises. Medications like Betahistine may be prescribed but have limited effectiveness in treating BPPV.

In infants who are less than 4 weeks old, it is recommended to measure their body temperature using an electronic thermometer placed in the armpit.

For children between the ages of 4 weeks and 5 years, there are several methods that can be used to measure body temperature. These include using an electronic thermometer in the armpit, a chemical dot thermometer in the armpit, or an infra-red tympanic thermometer.

It is important to note that measuring temperature orally or rectally should be avoided in this age group. Additionally, forehead chemical thermometers are not reliable and should not be used.

Ascending cholangitis occurs when there is an infection in the common bile duct, often caused by a stone that has led to a blockage of bile flow. This condition is characterized by the presence of Charcot’s triad, which includes jaundice, fever with rigors, and pain in the right upper quadrant of the abdomen. It is a serious medical emergency that can be life-threatening, with some patients also experiencing altered mental status and low blood pressure due to septic shock, known as Reynold’s pentad. Urgent biliary drainage is the recommended treatment for ascending cholangitis.

In acute cholecystitis, Murphy’s sign is typically positive, indicating tenderness in the right upper quadrant when the gallbladder is palpated. However, it is negative in cases of biliary colic and ascending cholangitis. The white cell count and C-reactive protein (CRP) levels are usually elevated in ascending cholangitis, along with the presence of jaundice and significantly increased levels of alkaline phosphatase (ALP) and bilirubin.

To differentiate between biliary colic, acute cholecystitis, and ascending cholangitis, the following can be helpful:

Biliary colic:
– Pain duration: Less than 12 hours
– Fever: Absent
– Murphy’s sign: Negative
– WCC & CRP: Normal
– AST, ALT & ALP: Normal
– Bilirubin: Normal

Acute cholecystitis:
– Pain duration: More than 12 hours
– Fever: Present
– Murphy’s sign: Positive
– WCC & CRP: Elevated
– AST, ALT & ALP: Normal or mildly elevated
– Bilirubin: Normal or mildly elevated

Ascending cholangitis:
– Pain duration: Variable
– Fever: Present
– Murphy’s sign: Negative
– WCC & CRP: Elevated
– AST, ALT & ALP: Elevated
– Bilirubin: Elevated