When there is damage to the facial nerve in the LMN, the patient will experience paralysis in the forehead and will be unable to wrinkle their brow. However, in an upper motor neuron lesion, the frontalis muscle is not affected, so the patient can still furrow their brow normally and their ability to close their eyes and blink is not affected. Lower motor neuron lesions affect the final part of the nerve pathway to all branches of the facial nerve, resulting in paralysis of the forehead and the rest of the face on that side. It is important to note that the speed of onset may provide some clues about the cause of the lesion, but it does not help determine the specific location of the damage.

Further Reading:

Bell’s palsy is a condition characterized by sudden weakness or paralysis of the facial nerve, resulting in facial muscle weakness or drooping. The exact cause is unknown, but it is believed to be related to viral infections such as herpes simplex or varicella zoster. It is more common in individuals aged 15-45 years and those with diabetes, obesity, hypertension, or upper respiratory conditions. Pregnancy is also a risk factor.

Diagnosis of Bell’s palsy is typically based on clinical symptoms and ruling out other possible causes of facial weakness. Symptoms include rapid onset of unilateral facial muscle weakness, drooping of the eyebrow and corner of the mouth, loss of the nasolabial fold, otalgia, difficulty chewing or dry mouth, taste disturbance, eye symptoms such as inability to close the eye completely, dry eye, eye pain, and excessive tearing, numbness or tingling of the cheek and mouth, speech articulation problems, and hyperacusis.

When assessing a patient with facial weakness, it is important to consider other possible differentials such as stroke, facial nerve tumors, Lyme disease, granulomatous diseases, Ramsay Hunt syndrome, mastoiditis, and chronic otitis media. Red flags for these conditions include insidious and painful onset, duration of symptoms longer than 3 months with frequent relapses, pre-existing risk factors, systemic illness or fever, vestibular or hearing abnormalities, and other cranial nerve involvement.

Management of Bell’s palsy involves the use of steroids, eye care advice, and reassurance. Steroids, such as prednisolone, are recommended for individuals presenting within 72 hours of symptom onset. Eye care includes the use of lubricating eye drops, eye ointment at night, eye taping if unable to close the eye at night, wearing sunglasses, and avoiding dusty environments. Reassurance is important as the majority of patients make a complete recovery within 3-4 months. However, some individuals may experience sequelae such as facial asymmetry, gustatory lacrimation, inadequate lid closure, brow ptosis, drooling, and hemifacial spasms.

Antiviral treatments are not currently recommended as a standalone treatment for Bell’s palsy, but they may be given in combination with corticosteroids on specialist advice. Referral to an ophthalmologist is necessary if the patient has eye symptoms such as pain, irritation, or itch.

Ophthalmia neonatorum refers to any cause of conjunctivitis during the newborn period, regardless of the specific organism responsible.

Conjunctivitis is the most frequent occurrence of Chlamydia trachomatis infection in newborns. Chlamydia is now the leading cause, accounting for up to 40% of cases. Neisseria gonorrhoea, on the other hand, only accounts for less than 1% of reported cases. The remaining cases are caused by non-sexually transmitted bacteria like Staphylococcus, Streptococcus, Haemophilus species, and viruses.

Gonorrhoeal ophthalmia neonatorum typically presents within 1 to 5 days after birth. It is characterized by intense redness and swelling of the conjunctiva, eyelid swelling, and a severe discharge of pus. Corneal ulceration and perforation may also be present.

Chlamydial ophthalmia neonatorum, on the other hand, usually appears between 5 to 14 days after birth. It is characterized by a gradually increasing watery discharge that eventually becomes purulent. The inflammation in the eyes is usually less severe compared to gonococcal infection, and there is a lower risk of corneal ulceration and perforation.

The second most common manifestation of Chlamydia trachomatis infection in newborns is pneumonia. Approximately 5-30% of infected neonates will develop pneumonia. About half of these infants will also have a history of ophthalmia neonatorum.

Clostridium difficile is a type of bacteria that is Gram-positive, anaerobic, and capable of forming spores. When individuals take broad-spectrum antibiotics, it can disrupt the normal bacteria in the bowel and allow C. difficile to multiply. This can lead to inflammation and bleeding in the mucosa of the large intestine, resulting in a distinct appearance known as pseudomembranous. The main symptoms of C. difficile infection (CDI) include abdominal cramps, bloody and/or watery diarrhea, and fever. It is worth noting that the majority of CDI cases occur in individuals over the age of 65.

CDI is considered to be the most severe consequence of antibiotic treatment and is now a significant cause of illness and death. While CDI can occur after treatment with any antibiotic, the risk is particularly high with prolonged use of broad-spectrum antibiotics. Recently, two research groups conducted a meta-analysis to assess the risk associated with different classes of antibiotics.

Their findings revealed that the risk of CDI increased nearly sevenfold after antibiotic treatment (odds ratio, 6.91). Among the various antibiotic classes, clindamycin posed the greatest risk (odds ratio, 20.43), followed by fluoroquinolones (odds ratio, 5.65), cephalosporins (odds ratio, 4.47), penicillins (odds ratio, 3.25), macrolides (odds ratio, 2.55), and trimethoprim/sulfonamides (odds ratio, 1.84). Tetracyclines, on the other hand, were not found to be associated with an increased risk of CDI (odds ratio, 0.91).

For more information on this topic, you may consider reading the article Antibiotic Classes and Risk for Clostridium difficile Infection.

Brown or reddish-brown discharge, which is commonly known as spotting, typically indicates the presence of blood in the fluid. It is important to approach any postmenopausal bleeding as a potential malignancy until proven otherwise.

When investigating cases of postmenopausal bleeding, the first-line examination is a transvaginal ultrasound (TVUS). This method effectively assesses the risk of endometrial cancer by measuring the thickness of the endometrium.

In postmenopausal women, the average endometrial thickness is significantly thinner compared to premenopausal women. The likelihood of endometrial cancer increases as the endometrium becomes thicker. In current practice in the UK, an endometrial thickness of 5 mm is considered the threshold.

If the endometrial thickness exceeds 5 mm, there is a 7.3% chance of endometrial cancer. However, if the endometrial thickness is uniformly less than 5 mm in a woman with postmenopausal bleeding, the likelihood of endometrial cancer is less than 1%.

In cases where there is a clinical suspicion of high risk, hysteroscopy and endometrial biopsy should also be performed. The definitive diagnosis is made through histological examination. If the endometrial thickness exceeds 5 mm, an endometrial biopsy is recommended.

The pupillary light reflex is a reflex that regulates the size of the pupil in response to the intensity of light that reaches the retina. It consists of two separate pathways, the afferent pathway and the efferent pathway.

The afferent pathway begins with light entering the pupil and stimulating the retinal ganglion cells in the retina. These cells then transmit the light signal to the optic nerve. At the optic chiasm, the nasal retinal fibers cross to the opposite optic tract, while the temporal retinal fibers remain in the same optic tract. The fibers from the optic tracts then project and synapse in the pretectal nuclei in the dorsal midbrain. From there, the pretectal nuclei send fibers to the ipsilateral Edinger-Westphal nucleus via the posterior commissure.

On the other hand, the efferent pathway starts with the Edinger-Westphal nucleus projecting preganglionic parasympathetic fibers. These fibers exit the midbrain and travel along the oculomotor nerve. They then synapse on post-ganglionic parasympathetic fibers in the ciliary ganglion. The post-ganglionic fibers, known as the short ciliary nerves, innervate the sphincter muscle of the pupils, causing them to constrict.

The result of these pathways is that when light is shone in one eye, both the direct pupillary light reflex (ipsilateral eye) and the consensual pupillary light reflex (contralateral eye) occur.

Lesions affecting the pupillary light reflex can be identified by comparing the direct and consensual reactions to light in both eyes. If the optic nerve of the first eye is damaged, both the direct and consensual reflexes in the second eye will be lost. However, when light is shone into the second eye, the pupil of the first eye will still constrict. If the optic nerve of the second eye is damaged, the second eye will constrict consensually when light is shone into the unaffected first eye. If the oculomotor nerve of the first eye is damaged, the first eye will have no direct light reflex, but the second eye will still constrict consensually. Finally, if the oculomotor nerve of the second eye is damaged, there will be no consensual constriction of the second eye when light is shone into the unaffected first eye.

This patient is exhibiting the psoas sign, which is a medical indication of irritation in the iliopsoas group of hip flexors located in the abdomen. In this particular case, it is highly likely that the patient has acute appendicitis.

The psoas sign can be observed by extending the patient’s thigh while they are lying on their side with their knees extended, or by asking the patient to actively flex their thigh at the hip. If these movements result in abdominal pain or if the patient resists due to pain, then the psoas sign is considered positive.

The pain occurs because the psoas muscle is adjacent to the peritoneal cavity. When the muscles are stretched or contracted, they rub against the inflamed tissues nearby, causing discomfort. This strongly suggests that the appendix is positioned retrocaecal.

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

There are two types of infectious agents that can lead to the development of a dendritic ulcer. The majority of cases (80%) are caused by the herpes simplex virus (type I), while the remaining cases (20%) are caused by the herpes zoster virus. To effectively treat this condition, the patient should follow a specific treatment plan. This includes applying acyclovir ointment topically five times a day for a duration of 10 days. Additionally, prednisolone 0.5% drops should be used 2-4 times daily. It is also recommended to take oral high dose vitamin C, as it has been shown to reduce the healing time of dendritic ulcers.

The key initial management for tension pneumothorax is needle thoracocentesis. This procedure is crucial as it rapidly decompresses the tension and allows for more definitive management to be implemented. It is important to note that according to ATLS guidelines, needle thoracocentesis should no longer be performed at the second intercostal space midclavicular line. Studies have shown that the fourth or fifth intercostal space midaxillary line is more successful in reaching the thoracic cavity in adult patients. Therefore, ATLS now recommends this location for needle decompression in adult patients.

Further Reading:

A pneumothorax is an abnormal collection of air in the pleural cavity of the lung. It can be classified by cause as primary spontaneous, secondary spontaneous, or traumatic. Primary spontaneous pneumothorax occurs without any obvious cause in the absence of underlying lung disease, while secondary spontaneous pneumothorax occurs in patients with significant underlying lung diseases. Traumatic pneumothorax is caused by trauma to the lung, often from blunt or penetrating chest wall injuries.

Tension pneumothorax is a life-threatening condition where the collection of air in the pleural cavity expands and compresses normal lung tissue and mediastinal structures. It can be caused by any of the aforementioned types of pneumothorax. Immediate management of tension pneumothorax involves the ABCDE approach, which includes ensuring a patent airway, controlling the C-spine, providing supplemental oxygen, establishing IV access for fluid resuscitation, and assessing and managing other injuries.

Treatment of tension pneumothorax involves needle thoracocentesis as a temporary measure to provide immediate decompression, followed by tube thoracostomy as definitive management. Needle thoracocentesis involves inserting a 14g cannula into the pleural space, typically via the 4th or 5th intercostal space midaxillary line. If the patient is peri-arrest, immediate thoracostomy is advised.

The pathophysiology of tension pneumothorax involves disruption to the visceral or parietal pleura, allowing air to flow into the pleural space. This can occur through an injury to the lung parenchyma and visceral pleura, or through an entry wound to the external chest wall in the case of a sucking pneumothorax. Injured tissue forms a one-way valve, allowing air to enter the pleural space with inhalation but prohibiting air outflow. This leads to a progressive increase in the volume of non-absorbable intrapleural air with each inspiration, causing pleural volume and pressure to rise within the affected hemithorax.

Aortic stenosis is a common condition where the valve in the heart becomes narrowed due to the progressive calcification that occurs with age. This typically occurs around the age of 70. Other causes of aortic stenosis include calcification of a congenital bicuspid aortic valve and rheumatic fever.

The symptoms of aortic stenosis can vary but commonly include difficulty breathing during physical activity, fainting, dizziness, chest pain (angina), and in severe cases, sudden death. However, it is also possible for aortic stenosis to be asymptomatic, meaning that there are no noticeable symptoms.

When examining a patient with aortic stenosis, there are several signs that may be present. These include a slow-rising and low-volume pulse, a narrow pulse pressure, a sustained apex beat, a thrill (a vibrating sensation) in the area of the aorta, and an ejection click if the valve is pliable. Additionally, there is typically an ejection systolic murmur, which is a specific type of heart murmur, that can be heard loudest in the aortic area (located at the right sternal edge, 2nd intercostal space) and may radiate to the carotid arteries.

It is important to differentiate aortic stenosis from aortic sclerosis, which is a degeneration of the aortic valve but does not cause obstruction of the left ventricular outflow tract. Aortic sclerosis can be distinguished by the presence of a normal pulse character and the absence of radiation of the murmur.