স্পেশাল বিসিএস (স্বাস্থ্য)

Pseudomembranous enterocolitis is caused by Cl. Difficile

Reference: Davidson 23rd; P-853
সলভ ক্লাসের জন্য আলোচনা পোস্ট দেখুন - [আলোচনা পোস্টের লিঙ্ক]

• Immunological competence of the fetus begins to develop at around 3 months. By this time the fetus makes all the components of the complement
• Maternal IgG begins to be transported from the mother to the fetus at approx 14 weeks (3.5 months)
• Newborns begin to produce their own antibody, but adult levels are not reached until the age of 3 years

Reference: Davidson 23rd; P-565

Ectodermal placodes are focal thickenings of the cranial ectoderm that generate many different components of the sensory systems of the head. Otic, nasal & lens placodes are found.

Reference: Davidson 23rd; P-816

Epithalamus includes pineal body, habenular nucleus and posterior commissure.

Stem Breakdown:

Fatigue, weight loss, and night sweats: These are "B symptoms," often seen in lymphomas.
Enlarged, non-tender lymph nodes in the cervical and axillary regions: Painless lymphadenopathy is a common presenting sign of lymphoma.
Option Analysis:

A) Hodgkin lymphoma: Hodgkin lymphoma typically presents with painless lymphadenopathy and "B symptoms," but it is more likely to involve mediastinal lymph nodes rather than widespread cervical and axillary nodes. The presence of Reed-Sternberg cells on biopsy confirms the diagnosis, but the stem lacks specific findings for Hodgkin lymphoma.
B) Non-Hodgkin lymphoma: This is the correct diagnosis. Davidson and Harrison explain that non-Hodgkin lymphoma (NHL) often presents with painless, generalized lymphadenopathy and systemic symptoms like weight loss and night sweats. NHL is more likely than Hodgkin lymphoma to cause widespread lymph node involvement.
C) Chronic lymphocytic leukemia (CLL): CLL causes painless lymphadenopathy and systemic symptoms, but it is also associated with an elevated white blood cell count (lymphocytosis), which is not mentioned in the case.
D) Tuberculosis: Tuberculosis can cause lymphadenopathy, particularly in the cervical region (scrofula), and systemic symptoms, but it typically presents with caseating granulomas on biopsy, and pulmonary involvement is common.

Ghrelin is released by the stomach.

Type I RTA is characterized by:

•Impaired hydrogen ion secretion in Distal  tubule
•Hypokalemia
•Hypocitraturia
•Hypercalciuria
•Nephrocalcinosis
•Renal Stones

Explanation: Osteophyte formation is characteristic of osteoarthritis, not rheumatoid arthritis. Davidson describes rheumatoid arthritis (RA) as a chronic autoimmune disease with symmetrical joint involvement, morning stiffness, and joint erosions visible on imaging. Harrison adds that RA is associated with systemic inflammation and can lead to joint deformity if untreated.

Explanation: There are 64 different codons with some redundancy in the system: 61 codons encode one of the 20 amino acids, and the remaining three codons – UAA, UAG and UGA (known as stop codons) – cause termination of the growing polypeptide chain.

Stem Breakdown:

Abdominal pain, bloody diarrhoea, and tenesmus: These are classic symptoms of ulcerative colitis (UC), which is an inflammatory bowel disease affecting the colon.
Continuous inflammation from the rectum to the sigmoid colon: UC is characterised by continuous inflammation starting in the rectum and extending proximally, often limited to the colon.
Option Analysis:

A) Ulcerative colitis: This is the correct diagnosis. Davidson and Harrison describe ulcerative colitis as a chronic inflammatory condition of the colon characterised by continuous inflammation, starting at the rectum and extending proximally. Bloody diarrhoea, abdominal pain, and tenses are hallmark symptoms. UC is often limited to the mucosa and submucosa of the colon, distinguishing it from Crohn's disease.
B) Crohn’s disease: Crohn's disease can affect any part of the gastrointestinal tract and is characterised by "skip lesions" (areas of normal bowel between inflamed segments). It also often involves transmural (full-thickness) inflammation, which can lead to complications like fistulas and strictures. The continuous inflammation seen in this patient is more typical of UC.
C) Irritable bowel syndrome (IBS): IBS causes abdominal pain and altered bowel habits (diarrhoea or constipation), but it does not cause bloody diarrhoea or visible inflammation on colonoscopy. IBS is a functional gastrointestinal disorder, not an inflammatory disease.
D) Diverticulitis: Diverticulitis presents with localised left lower quadrant pain, fever, and leukocytosis, typically without bloody diarrhoea or continuous inflammation on colonoscopy.

Reference: Davidson 23rd; P-417

The history in this case suggests the patient's chest pain is due to muscular injury rather than anything more sinister. The patient's anxiety about cardiovascular morbidity has ultimately resulted in hyperventilation causing an acute respiratory alkalosis . Acid base abnormalities can be solved by either considering the Henderson-Hasselbach equation (CO2 + H2O → H2CO3 → H+ + HCO3-), whereby change in the product(s) on one side of the equation is balanced by a shift in equilibrium. For example, in this case the patient's hyperventilation causes a reduction in CO2, in order to increase the CO₂ the equilibrium shifts towards CO₂ + H₂O which causes a reduction in H+ (alkalosis) and HCO3-. This process occurs in respiratory alkalosis with metabolic compensation (C). If the patient had a true cardiac arrest it would cause a surge in lactic acidosis hence H+ concentration increases causing a metabolic acidosis (B). In order to balance this change, the equilibrium shifts away from H+ and causes increased CO2 production which can manifest as an increased respiratory rate, otherwise called 'metabolic acidosis with respiratory compensation' (D). In a respiratory acidosis with metabolic compensation (A) scenario, a patient may have a respiratory abnormality such as chronic hypoventilation. The accumulation of CO2 which leads to increased H+ is compensated for by bicarbonate which is subsequently reduced. In more chronic conditions, the bicarbonate becomes elevated.

Vit-k dependent blood clotting factors
 1. Factor ll(prothrombin)
2. Factor Vll
3. Factor IX  
4. Factor X

Reference: Davidson 23rd; P-572

Hepatitis B surface antigen
Hepatitis B surface antigen (HBsAg) is the main indicator of active infection, and a negative test for HBsAg makes HBV infection very unlikely.

RNA three types

Messenger RNA , Ribosomal RNA, Transfer RNA

Reference: Davidson 23rd; P-813

 Pregnancy is the most common cause of secondary amenorrhea (the absence of menstruation for more than three cycles in a previously menstruating woman). Davidson emphasizes that pregnancy should always be ruled out first in women presenting with amenorrhea. Harrison adds that other common causes of secondary amenorrhea include polycystic ovary syndrome (PCOS), hyperprolactinemia, and thyroid disorders.

Explanation: Chronic gastric ulcer is usually single; 90% are situated on the lesser curve within the antrum or at the junction between body and antral mucosa

HAV and HEV are transmitted via the faeco-oral route, especially in areas with poor sanitation.

Collections of neuronal cell bodies (somata) outside the central nervous system is Ganglia & inside CNS is Nuclei.

[Ref. Junqueira 15th] 

Ref: Davidson 23rd; P- 921(Box-23.2)

Explanation: ACE inhibitors & ARB are contraindicated in pregnancy

Explanations:
Serum contains no fibrinogen

Microtubules are non branching hollow tubules made up of tubulin proteins (α and b tubulin) with a diameter of 25 nm

Locations:
• Cilia
• Flagella
• Centrioles
• Mitotic spindle
• Elongating cell processes and
• Growing axons

Functions:
1. Movement of cilia, flagella (tail of sperm)
2. Intracellular transport of vesicles
3. In cell division, formation of mitotic spindle
4. Maintenance of cell shape

[Ref. Junquira 15th, 43]

Predominant acute inflammatory cell in first 24 hours is neutrophil

Explanation:

[Robbins 9th 293]

A.Duodenale enters through skin penetration

Reference: Guyton 14th; P- 491

In the upper extremity, shoulder and wrists ends of the bones are the growing ends. In the lower extremity, knee ends of femur, tibia, fibula are the growing ends.

Medulloblastoma is childhood tumour in cerebellam

Type B: Impaired Lactic acid  metabolism
•Severe sepsis
•Hepatic & Renal failure
•Drugs- Metformin, Ethanol
•Diabetes mellitus
Type A: Increased production, due to:
Hypotension – Shock, Cardiac failure
Tissue hypoxia:
Mitochondrial  dysfunction (CO, Cyanide) Severe anemia

Explanations:
The cell and the intracellular organelles are surrounded by semipermeable membranes. Biological membranes have a lipid bilayer core that is populated by structural and functional proteins. These proteins contribute greatly to the semipermeable properties of biological membrane.

Explanation :
Physiological giant cell -
Osteoclast
Megakaryocytes
Syncytiotrophoblast of placenta
Pathological giant cell-
Anaplastic tumors
Hodgkin's disease
Choriocarcinoma
Poorly differentiated astrocytoma
Primary billiary cirrhosis
Giant cell of herpes simplex virus 

Fibrinoid necrosis is seen in SLE

Explanation: Insulin causes hypokalaemia, option A,B,D Drugs causes hyperkalaemia

IFN-γ is the critical mediator that enables macrophages to contain the M. tuberculosis infection.

Mild
 Hydrocortisone 0.5%, 1%, 2.5%
 Hydrocortisone 1% and fusidic acid 2% (Fucidin H)
Potent
 Betamethasone valerate 0.1% (Betnovate)  Betamethasone valerate 0.1% and clioquinol 3% (Betnovate-C)  Fluocinolone acetonide 0.025% (Synalar)  Hydrocortisone butyrate 0.1% (Locoid)  Mometasone furoate 0.1% (Elocon)

Explanation: Blood culture is the specific investigation for thyphoid fever

Botulinum toxin block the release of acetylcholine & produces descending weakness & paralysis.

Major criterias are:

Arthritis
Carditis 
Chorea
Erythema marginatum
Subcutaneous nodule

Explanation: Hypertensive heart disease can affect either the left ventricle or the right ventricle; the latter is called cor pulmonale

Vomiting without nausea–raised intracranial pressure (ICP)
Projectile vomiting–gastric outlet obstruction
Pain abdomen relieved by vomiting–gastric ulcer
Vomiting with absolute constipation–intestinal obstruction

Type III collagen produces a network of delicate reticular fibers, which stain very dark with silver stains and are abundant in immune and lymphoid tissues.

Central obesity (truncal fat, moon face, buffalo hump) is a classic feature of Cushing’s syndrome due to excess cortisol. Weight loss is seen in adrenal insufficiency, and hypertension (not hypotension) and tachycardia (not bradycardia) are common

T. solium can affects CNS

The major unmeasured cations are calcium,  magnesium, gamma globulins.

Explanation:
Stem Breakdown:

Sudden-onset weakness and difficulty speaking: These are classic signs of a stroke.
CT showing ischaemia in the left middle cerebral artery (MCA): This confirms that the stroke is ischaemic in nature.
Option Analysis:

A) Transient ischaemic attack (TIA): A TIA involves brief episodes of neurological dysfunction caused by temporary ischaemia without infarction. In this case, the CT scan shows ischaemia, indicating tissue damage, which rules out TIA.
B) Ischaemic stroke: This is the correct diagnosis. Davidson and Harrison explain that ischaemic strokes are caused by obstruction of a cerebral artery, leading to tissue infarction. Sudden-onset weakness (hemiparesis) and difficulty speaking (aphasia) are typical of a left MCA stroke.
C) Hemorrhagic stroke: Hemorrhagic stroke involves bleeding into the brain tissue, often presenting with a more severe clinical picture, including altered consciousness, headache, and vomiting. In this case, the CT shows ischaemia rather than haemorrhage.
D) Subdural haematoma: Subdural haematoma results from venous bleeding, typically following head trauma, and presents with a gradual onset of symptoms like confusion and headache. It does not present with acute ischaemic findings on CT.

Explanation: HIV-associated neurocognitive disorder (HAND) is the most common neurological complication in HIV-infected individuals, as described by Davidson. Cognitive deterioration, motor impairment, and behavioural abnormalities are all possible signs of HAND. Harrison emphasises that although antiretroviral therapy (ART) has reduced the incidence of severe forms, mild cognitive impairment remains common.