The patient has a primary psoas abscess.

Psoas (or iliopsoas) abscess is a collection of pus in the iliopsoas muscle compartment. It may arise via contiguous spread from adjacent structures or by the haematogenous route from a distant site. Psoas abscesses may be either primary or secondary. Primary cases often develop in the immunosuppressed and may occur as a result of haematogenous spread. Secondary cases may occur as a complication of intra-abdominal diseases such as Crohn’s disease.

Patients usually present with lower back pain and if the abscess is extensive, a mass that may be localised to the inguinal region or femoral triangle. In most cases, the diagnosis can be made clinically. Where it is not clear, an ultrasound scan is often the most convenient investigation.

Smaller collections may be percutaneously drained. If the collection is larger, or the percutaneous route fails, then surgery (via a retroperitoneal approach) should be performed.

Pneumothorax is the most common complication of a fine-needle aspiration procedure. Various factors, such as lesion size, have been associated with increased risk of pneumothorax .

Branchial cleft cysts are congenital anomalies that usually arise from second cleft/pouch, with remnants of the third and fourth pouch are rare. Children are typically born with these congenital lesions; however, they may not be evident for weeks, months, or possibly years. The lesions present as fistulae, cyst, sinus tracts, or cartilaginous remnants due to incomplete obliteration during embryogenesis.

They are often asymptomatic, but can often become tender, enlarged, or inflamed with possible abscess formation during episodes of upper respiratory tract infections.
The patient can present with purulent drainage of the sinus to skin or pharynx from spontaneous rupture of branchial cleft cyst abscess. The most concerning symptoms include dysphagia, dyspnoea, and stridor due to cyst compression of the upper airway.

The physical examination will differ depending on the location of the branchial cleft cyst:
– A primary branchial cleft cyst is typically smooth, non-tender, fluctuant mass found between the external auditory canal and submandibular area. It is usually with the parotid gland and facial nerve. Two types of lesions exist. Type 1 is rare and characterized as duplication of the membranous external auditory canal. Type 2 lesions contain both ectoderm and mesoderm elements including cartilage. The patient usually presents with soft tissue mass or draining sinus located on the angle of the mandible or otorrhea, making an otologic exam critical in these cases.
– A secondary branchial cleft cyst is located between the lower anterior border of the sternocleidomastoid and the tonsillar fossa of the pharynx. It can be in proximity to the glossopharyngeal and hypoglossal nerve as well as carotid vessels. Compared to the primary branchial cleft cysts, secondary cysts are tender if secondarily inflamed or infected. If it is associated with a sinus tract, a mucoid or purulent discharge may be present on the skin or into the pharynx.

The treatment of a branchial cleft cyst is typically elective excision due to the risk of infection or present infection, further enlargement, or malignancy.

– Carotid Body Tumour: Painless oropharyngeal or upper anterior triangle of the neck; pulsatile, compressible with a bruit or thrill, mobile from medial to lateral direction.
– Bartonella henselae infection is Isolated, mobile, fluctuant, tender, warm, erythematous, > 2 cm near the site of inoculation.
– Thyroglossal duct cyst: In the Midline, adjacent to the hyoid bone; rises with deglutition.

The suprarenal veins or also known as the veins of Warshaw, are the veins that receive blood from the suprarenal glands. These veins receive blood from the medullary venous plexus and the cortex of the adrenal glands (suprarenal glands). They are two in number – the left and the right suprarenal veins. The right suprarenal vein drains into the inferior vena cava while the left suprarenal vein drains into the left renal vein. This therefore means that in the case of a metastasizing tumour involving the left suprarenal vein, the tumour will most likely extend from the left suprarenal vein to the left renal vein into which it drains.

Pelvic inflammatory disease (PID) is an infectious and inflammatory disorder of the upper female genital tract, including the uterus, fallopian tubes, and adjacent pelvic structures. Infection and inflammation may spread to the abdomen, including perihepatic structures (Fitz-Hugh−Curtis syndrome). The classic high-risk patient is a menstruating woman younger than 25 years who has multiple sex partners, does not use contraception, and lives in an area with a high prevalence of sexually transmitted disease (STD).
PID is initiated by an infection that ascends from the vagina and cervix into the upper genital tract. Chlamydia trachomatis is the predominant sexually transmitted organism associated with PID. Of all acute PID cases, less than 50% test positive for the sexually transmitted organisms such as Chlamydia trachomatis and Neisseria gonorrhoea.
Other organisms implicated in the pathogenesis of PID include Gardnerella vaginalis (which causes bacterial vaginosis (BV), Haemophilus influenzae, and anaerobes such as Peptococcus and Bacteroides species. Laparoscopic studies have shown that in 30-40% of cases, PID is polymicrobial.
The most common presenting complaint is lower abdominal pain. Abnormal vaginal discharge is present in approximately 75% of cases. Unanticipated vaginal bleeding, often postcoital, is reported in about 40% of cases. Temperature is higher than 38°C (found in 30% of cases), nausea, and vomiting manifest late in the clinical course of the disease. Abnormal uterine bleeding is present in more than one-third of patients.
Right upper quadrant tenderness, especially if associated with jaundice, may indicate associated Fitz-Hugh−Curtis syndrome.

The major duodenal papilla is on the descending portion of the duodenum on the medial side, about 7-10cm from the pylorus. The pancreatic ducts and the common bile ducts unite and open by a common orifice on the summit of the duodenal papilla.

Mirizzi syndrome is defined as common hepatic duct obstruction caused by extrinsic compression from an impacted stone in the cystic duct or infundibulum of the gallbladder. Patients with Mirizzi syndrome can present with jaundice, fever, and right upper quadrant pain. Mirizzi syndrome is often not recognized preoperatively in patients undergoing cholecystectomy and can lead to significant morbidity and biliary injury, particularly with laparoscopic surgery. Acute presentations of the syndrome include symptoms consistent with cholecystitis.
Surgery is extremely difficult as Calot’s triangle is often completely obliterated and the risks of causing injury to the common bile duct (CBD) are high.
Multiple and large gallstones can become impacted in the Hartmann’s pouch of the gallbladder, leading to chronic inflammation – which leads to compression of the CBD, necrosis, fibrosis, and ultimately fistula formation into the adjacent common hepatic duct (CHD). As a result, the CHD/CBD becomes obstructed by either scar or stone, resulting in obstructive jaundice. It can be divided into four types.
Type I – No fistula present
Type IA – Presence of the cystic duct
Type IB – Obliteration of the cystic duct
Types II–IV – Fistula present
Type II – Defect smaller than 33% of the CHD diameter
Type III – Defect 33–66% of the CHD diameter
Type IV – Defect larger than 66% of the CHD diameter

Simple cholecystectomy is suitable for type I patients. For types II–IV, subtotal cholecystectomy can be performed to avoid damage to the main bile ducts. Cholecystectomy and bilioenteric anastomosis may be required. Roux-en-Y hepaticojejunostomy has shown good outcome in some studies.

Spherocytes are small rounded RBCs. It is due to an inherited defect of the RBC cytoskeleton membrane tethering proteins. Membrane blebs form that are lost over time and cells become round instead of biconcave. As it is a normochromic anaemia, the MCV is normal. it is diagnosed by osmotic fragility test which reveals increased fragility in a hypotonic solution.

Hypoxic pulmonary vasoconstriction is a local response to hypoxia resulting primarily from constriction of small muscular pulmonary arteries in response to reduced alveolar oxygen tension. This unique response of pulmonary arterioles results in a local adjustment of perfusion to ventilation. This means that if a bronchiole is obstructed, the lack of oxygen causes contraction of the pulmonary vascular smooth muscle in the corresponding area, shunting blood away from the hypoxic region to better-ventilated regions. The purpose of hypoxic pulmonary vasoconstriction is to distribute blood flow regionally to increase the overall efficiency of gas exchange between air and blood.

Mycosis fungoides is a chronic T-cell lymphoma that involves the skin and less commonly, the internal organs such as nodes, liver, spleen and lungs. It is usually diagnosed in patients above 50 years and the average life expectancy is 7-10 years. It is insidious in onset and presents as a chronic, itchy rash, eventually spreading to involve most of the skin. Lesions are commonly plaque-like, but can be nodular or ulcerated. Symptoms include fever, night sweats and weight loss. Skin biopsy is diagnostic. However, early cases may pose a challenge due to fewer lymphoma cells. The malignant cells are mature T cells (T4+, T11+, T12+). The epidermis shows presence of characteristic Pautrier’s micro abscesses are present in the epidermis.

Schwannomas are histologically benign neoplasms that arise from nerve sheaths, most commonly from sensory nerve roots. They are generally contained within a capsule, and so can be surgically removed without injuring the associated nerve root. They are histologically benign and less than 1% become malignant.

Haemophilia C, also known as plasma thromboplastin antecedent (PTA) deficiency or Rosenthal syndrome, is a condition caused by the deficiency of the coagulation factor XI. The condition is rare and it is usually found in Ashkenazi Jews.

The laryngeal airway mask (LAM) is a device for anaesthetic air way management. The primary advantage of the laryngeal airway mask (LAM) over the face mask during general anaesthesia includes the ability to obtain, secure, and maintain a patent airway. The laryngeal mask airway is passed beyond the tongue, forming a seal with the laryngeal inlet and eliminating the most common cause of upper airway obstruction in the non-intubated patient.

Maintenance of a patent airway with fewer episodes of oxygen desaturation has been demonstrated for the LAM as compared with the face mask. Environmental inhalational gas exposure values associated with the use of a LAM have been shown to be less than those achieved with a face mask and comparable to those with the use of an endotracheal tube. Ocular and facial nerve injuries associated with prolonged face mask use are also avoided. The advantages of the laryngeal mask airway include anaesthetic management, induction, maintenance, and emergence.

The placement of the LMA can be accomplished without muscle relaxants and laryngoscopy. The avoidance of succinylcholine may decrease the incidence of post-operative myalgias. Significant and potentially detrimental hemodynamic changes associated with both laryngoscopy and tracheal intubation are also attenuated and are of shorter duration with the use of the laryngeal mask airway. Compared with an endotracheal tube, the anaesthetic requirement for tolerance of the LAM has also been reported to be less. Differences in the response to the LAM are also seen during emergence from anaesthesia. The LAM is well tolerated, with a lower reported incidence of hyperactive respiratory occurrences (e.g., coughing, laryngospasm, breath holding) than with an endotracheal tube. The anatomic placement of the LAM, with its lack of impingement on the trachea and vocal cords, minimizes complications that are potentially associated with intubation. According to Swann et al. incidence of postoperative sore throat as well as hoarseness is less with the LAM compared with the endotracheal tube.

The AJCC uses a TNM system to stage prostatic cancer, with categories for the primary tumour, regional lymph nodes and distant metastases:
TX: cannot evaluate the primary tumour T0: no evidence of tumour
T1: tumour present, but not detectable clinically or with imaging T1a: tumour was incidentally found in less than 5% of prostate tissue resected (for other reasons)
T1b: tumour was incidentally found in more than 5% of prostate tissue resected
T1c: tumour was found in a needle biopsy performed due to an elevated serum prostate-specific antigen
T2: the tumour can be felt (palpated) on examination, but has not spread outside the prostate
T2a: the tumour is in half or less than half of one of the prostate gland’s two lobes
T2b: the tumour is in more than half of one lobe, but not both
T2c: the tumour is in both lobes
T3: the tumour has spread through the prostatic capsule (if it is only part-way through, it is still T2)
T3a: the tumour has spread through the capsule on one or both sides
T3b: the tumour has invaded one or both seminal vesicles
T4: the tumour has invaded other nearby structures.
In this case, the tumour has a T1c stage.

Complications of Transurethral Resection: TURP
T URP syndrome
U rethral stricture/UTI
R etrograde ejaculation
P erforation of the prostate

TURP syndrome can cause a wide variety of symptoms that include asymptomatic hyponatremia, ECG changes, fatigue, vomiting, confusion, visual loss, coma and death. In a conscious and alert patient, changes in the mental state of may be the first sign of TURP syndrome and bladder perforation.

The internal auditory meatus is a canal within the petrous part of the temporal bone of the skull between the posterior cranial fossa and the inner ear. It provides a passage through which the vestibulocochlear nerve, the facial nerve, and the labyrinthine artery (an internal auditory branch of the basilar artery) can pass from inside the skull to structures of the inner ear and face.

Gastric blood flow is increased by vagal stimulation, gastrin, histamine and acetylcholine as they stimulate gastric section and the production of vasodilator metabolites. Acetylcholine and histamine also have a direct action on the gastric arterioles. Similarly, gastric blood flow is reduced by inhibitors of secretion – catecholamines, secretin and vasopressin.

Acidosis with high p(CO2) and normal standard bicarbonate indicates respiratory acidosis, commonly seen in acute worsening of COPD patients. Respiratory acidosis occurs due to alveolar hypoventilation which leads to increased arterial carbon dioxide concentration (p(CO2)). This in turn decreases the HCO3 –/p(CO2) and decreases pH. In acute respiratory acidosis, the p(CO2) is raised above the upper limit of normal (over 45 mm Hg) with a low pH. However, in chronic cases, the raised p(CO2) is accompanied with a normal or near-normal pH due to renal compensation and an increased serum bicarbonate (HCO3 – > 30 mmHg).

Papillary thyroid carcinoma is the most common thyroid cancer. This cancer has a high cure rate with 10-year survival rates for all patients with papillary thyroid cancer estimated at 80% to 90%.

A gastrinoma is a gastrin-secreting tumour that can occur in the pancreas, although it is most commonly found in the duodenum. Duodenal wall gastrinomas have been identified in 40-50% of patients. These duodenal wall tumours are frequently small and multiple. Sporadic tumours occurring in the pancreas tend to be solitary and have a greater malignant potential as compared to duodenal gastrinomas.

Primary tumours also occur in a variety of ectopic sites, including the body of the stomach, jejunum, peripancreatic lymph nodes, splenic hilum, omentum, liver, gallbladder, common bile duct, and the ovary. Over 50% of gastrinomas are malignant and can metastasize to the regional lymph nodes and the liver. One fourth of gastrinomas are related to multiple endocrine neoplasia (MEN) type I and are associated with hyperparathyroidism and pituitary adenomas.

The symptoms in 90-95% of patients with gastrinomas are similar to the symptoms of common peptic ulcer disease. Usually, persistent abdominal pain exists that is less responsive to medical treatment.
Sometimes, symptoms may relate to a complication of peptic ulcer disease, such as bleeding (e.g., melena, hematemesis), gastric outlet obstruction (e.g., vomiting), and perforation (e.g., peritoneal irritation).
Other symptoms include gastroesophageal reflux, diarrhoea, steatorrhea, and weight loss, all of which are secondary to acid hypersecretion. Vitamin B-12 malabsorption, which is not correctable by oral intrinsic factor, may also be observed.

Somatostatin receptor scintigraphy (SRS) is very useful to identify the primary lesions preoperatively. SRS is the most sensitive non-invasive method for localizing the primary tumours and metastases. It also is helpful for detecting the presence of liver or bone metastasis.

Bronchioloalveolar carcinoma (BAC) is a term used to define a particular subtype of adenocarcinoma which develops in cells near the alveoli, in the outer regions of the lungs. On a chest X-ray it can appear as a single peripheral spot or as scattered spots throughout the lungs. Symptoms include cough, haemoptysis, chest pain, dyspnoea and loss of weight.

Capillaries are the smallest of the body’s blood vessels, measuring 5–10 μm and they help to enable the exchange of water, oxygen, carbon dioxide, and many other nutrients and waste substances between the blood and the tissues surrounding them. The walls of capillaries are composed of only a single layer of cells, the endothelium. Ion channels are pore-forming proteins that help to establish and control the small voltage gradient that exists across the plasma membrane of all living cells by allowing the flow of ions down their electrochemical gradient. An ion channel is an integral membrane protein or more typically an assembly of several proteins. The archetypal channel pore is just one or two atoms wide at its narrowest point. It conducts a specific ion such as sodium or potassium and conveys them through the membrane in single file.

The digastric muscle is a small muscle located under the jaw. It lies below the body of the mandible, and extends, in a curved form, from the mastoid process to the symphysis menti. The digastric divides the anterior triangle of the neck into three smaller triangles:
– The submaxillary triangle, bounded above by the lower border of the body of the mandible and a line drawn from its angle to the sternocleidomastoid, below by the posterior belly of the digastric and the stylohyoid and in front by the anterior belly of the digastric
– The carotid triangle, bounded above by the posterior belly of the digastric and stylohyoid, behind by the sternocleidomastoid and below by the omohyoid
– The suprahyoid or submental triangle, bounded laterally by the anterior belly of the digastric, medially by the midline of the neck from the hyoid bone to the symphysis menti and inferiorly by the body of the hyoid bone.

The linea aspera is a prominent longitudinal ridge or crest on the middle third of the femur. It has a medial and a lateral lip and a narrow, rough, intermediate line. The vastus medialis arises from the medial lip of the linea aspera and has superior and inferior prolongations. The vastus lateralis takes origin from the lateral lip . The adductor magnus is inserted into the linea aspera. Two muscles are attached between the vastus lateralis and the adductor magnus: the gluteus maximus is inserted above and the short head of the biceps femoris arises below. Four muscles are inserted between the adductor magnus and the vastus medialis: the iliacus and pectineus superiorly, and the adductor brevis and adductor longus inferiorly.

Allograft coronary artery disease (CAD) can begin right after the transplant and is the major cause of later death in cardiac transplant recipients. This form of atherosclerosis progresses quickly resulting in allograft failure. Due to lack of premonitory symptoms CAD may lead to sudden death.

Complications of ERCP include pancreatitis, duodenal perforation, duodenal haemorrhage, infection, stent migration, and complications secondary to endoscopy. CT is performed if patients have severe abdominal pain, jaundice, elevated white blood cell count, and fever after ERCP.

Hemianopia or hemianopsia, is the loss of vision of half of the eye or loss of half the visual field. Homonymous hemianopia is the loss of vision or blindness on half of the same side of both eyes (visual field) – either both lefts of the eyes or both rights of the eyes. This condition is mainly caused by cerebrovascular accidents like a stroke that affects the optic radiation.

Vestibular neuronitis or labyrinthitis causes a self-limited episode of vertigo, presumably due to inflammation of the vestibular division of cranial nerve VIII. Its causes are unknown, It may be due to a virus, but it can be related to a bacterial infection, head injury, stress, allergy, or as a reaction to medication. Symptoms can last up to 7-10 days.

As the inferior gluteal nerve emerges from the greater sciatic foramen below the piriformis muscle, it divides into branches and enters the gluteus maximus muscle which extends the femur and bends the thigh in line with the body.

Hyperacute rejection occurs almost immediately following organ implantation and necessitates immediate explant of the organ. Hyperacute rejection is uncommon with pre-transplantation cross-matches and screening. Hyperacute rejection (HAR) of the kidney was first recognized 20 years ago in cases of donor-recipient incompatibility for the major blood group and tissue antigen systems. Classic pathological changes described include early accumulation of PMNs in glomeruli and peritubular capillaries, progressive glomerular thrombosis, tubular necrosis, and eventual cortical necrosis. Reaction of host humoral antibodies with antigens on donor cells serves as one trigger of the clotting mechanism, which then proceeds in a nonspecific fashion.

Antigen systems other than the ABO groups that contribute to HAR reactions are leukocyte antigens, endothelial and monocyte antigens, and B cell antigens. It is also documented that glomerular thrombosis identical to HAR may occur secondary to endothelial damage after pulsatile perfusion. However, in such cases no specific deposition of immunoglobulins and complement is detected.