1.
Antibody mediated glomerular injury can be evaluated by utilizing immunofluorescence. A granular pattern is seen with
Correct Answer
D. Deposition of immune complexes
Explanation
Antibody mediated glomerular injury can be evaluated using immunofluorescence, which helps in visualizing the deposition of various components involved in the immune response. In this case, the correct answer is the deposition of immune complexes. Immune complexes are formed when antibodies bind to antigens, and their deposition in the glomerulus can lead to inflammation and injury. Immunofluorescence can detect the presence of these immune complexes and help in diagnosing antibody mediated glomerular injury.
2.
A 20‑year‑old female presented with generalized CNS signs and symptoms. A lumbar puncture revealed the CSF to exhibit a lymphocytic pleocytosis. She became comatose and expired one week after the onset of symptoms. Histologic sections taken from the brain at autopsy would MOST LIKELY reveal:
Correct Answer
B. Perivascular lympHocytic infiltrates & microglial nodules
Explanation
The presentation of generalized CNS signs and symptoms, along with a lymphocytic pleocytosis in the CSF, suggests an inflammatory process in the central nervous system. The presence of perivascular lymphocytic infiltrates and microglial nodules is characteristic of an inflammatory response, indicating an infectious or autoimmune etiology. This finding is commonly seen in conditions such as viral encephalitis, autoimmune encephalitis, or CNS vasculitis. The other options, such as Lewy bodies (seen in Parkinson's disease), spongiform change (seen in prion diseases), neuritic plaques, and neurofibrillary tangles (seen in Alzheimer's disease), and demyelination (seen in multiple sclerosis), are not consistent with the clinical presentation and CSF findings described.
3.
A 40‑year‑old female presented with weakness of the extraocular muscles often accompanied by diplopia. She also exhibited ptosis, as well as generalized muscle weakness. The weakness fluctuated in severity throughout the day. The patient's weakness improved dramatically after administration of Tensilon (a short‑acting anticholinesterase). Patients with this condition often have associated pathology in which of the following glands?
Correct Answer
D. Thymus gland
Explanation
Patients with weakness of the extraocular muscles, diplopia, ptosis, and generalized muscle weakness that improves after administration of Tensilon likely have myasthenia gravis. Myasthenia gravis is an autoimmune disorder characterized by the presence of antibodies against the acetylcholine receptors at the neuromuscular junction. The thymus gland is often involved in the pathogenesis of myasthenia gravis, with approximately 70% of patients having thymic abnormalities such as thymic hyperplasia or thymoma. Therefore, the correct answer is Thymus gland.
4.
A 65‑year‑old female developed a progressive dementia accompanied by ataxia. The patient expired 18 months after the onset of symptoms. At autopsy, spongiform degeneration was noted in the cerebral and cerebellar cortices. No cerebrovascular disease, neurofibrillary tangles or foci of demyelination were noted. The MOST LIKELY diagnosis is:
Correct Answer
A. Creutzfeldt Jakob Disease
Explanation
The most likely diagnosis in this case is Creutzfeldt Jakob Disease. This is supported by the progressive dementia and ataxia exhibited by the patient, as well as the presence of spongiform degeneration in the cerebral and cerebellar cortices at autopsy. The absence of cerebrovascular disease, neurofibrillary tangles, and foci of demyelination rules out other possibilities such as Alzheimer's Disease, Multi infarct Dementia, Huntington Disease, and Progressive Multifocal Leukoencephalopathy.
5.
A 42‑year‑old AIDS patient presented with multifocal neurologic signs and symptoms. His neurologic status progressively deteriorated and he expired six months after the onset of symptoms. At autopsy, there were discrete patches of demyelination scattered throughout the white matter. Only small numbers of oligodendrocytes could be identified in the areas of demyelination and anaplastic astrocytes were also noted. The MOST LIKELY diagnosis is:
Correct Answer
B. Progressive Multifocal LeukoencepHalopathy
Explanation
The most likely diagnosis in this case is Progressive Multifocal Leukoencephalopathy (PML). PML is a rare viral infection of the brain caused by the JC virus. It primarily affects immunocompromised individuals, such as AIDS patients. The clinical presentation of multifocal neurologic signs and symptoms, along with the progressive deterioration of neurologic status and death within six months, is consistent with PML. The presence of discrete patches of demyelination scattered throughout the white matter, along with the identification of small numbers of oligodendrocytes and anaplastic astrocytes, further supports the diagnosis of PML.
6.
In patients with Alzheimer Disease, the pathogenesis currently is believed to be related to an
Correct Answer
A. Accumulation of amyloid beta peptide within CNS neurons
Explanation
In patients with Alzheimer's Disease, the accumulation of amyloid beta peptide within CNS neurons is believed to be the cause of the pathogenesis. This accumulation leads to the formation of plaques, which disrupt the normal functioning of neurons and ultimately leads to cognitive decline and memory loss. The amyloid beta peptide is derived from the breakdown of a larger protein called amyloid precursor protein (APP). When APP is cleaved by enzymes, it produces amyloid beta peptide, which can then aggregate and form plaques. These plaques interfere with neuronal communication and contribute to the development and progression of Alzheimer's Disease.
7.
40‑year‑old Caucasian male of European decent developed the gradual onset of involuntary jerky movements involving the entire body. He also developed a progressive dementia. His father died from this same disorder at age 58. The pathogenesis of this patient's disease process is MOST LIKELY related to
Correct Answer
C. A trinucleotide repeat expansion mutation in the gene encoding huntingtin
Explanation
The correct answer is a trinucleotide repeat expansion mutation in the gene encoding huntingtin. This is because the patient's symptoms of involuntary jerky movements and progressive dementia are characteristic of Huntington's disease, which is caused by an abnormal expansion of the trinucleotide repeat in the huntingtin gene. This mutation leads to the production of a mutant huntingtin protein, which accumulates in the brain and causes neurodegeneration. The patient's family history of the same disorder further supports this diagnosis.
8.
A 50‑year‑old male who had been involved in a motor vehicle accident presented with a dilated pupil and paralysis of ocular movements on the right. His mental status rapidly deteriorated and he expired. Pertinent autopsy findings included an area of acute infarction in the right occipital lobe, as well as hemorrhages in the pons and midbrain. These clinicopathologic findings are MOST consistent with
Correct Answer
B. Right uncal herniation
Explanation
The patient presented with a dilated pupil and paralysis of ocular movements on the right side, indicating dysfunction of the oculomotor nerve. The rapid deterioration in mental status and subsequent death suggest increased intracranial pressure. Autopsy findings of acute infarction in the right occipital lobe, as well as hemorrhages in the pons and midbrain, are consistent with herniation of the right uncus (uncal herniation). Uncal herniation occurs when the medial aspect of the temporal lobe herniates through the tentorial notch, compressing the oculomotor nerve and causing midbrain compression. This leads to pupillary dilation, paralysis of ocular movements, and subsequent brainstem hemorrhages.
9.
A 70‑year‑old man presented with decreased facial expression, shuffling gait, slowness of voluntary movements, rigidity and a "pill‑rolling" tremor. He died suddenly from an unrelated coronary event. Examination of this patient's brain at autopsy would reveal which of the following?
Correct Answer
B. Lewy bodies and decreased numbers of pigmented neurons in the substantia nigra
Explanation
The presentation of decreased facial expression, shuffling gait, slowness of voluntary movements, rigidity, and a "pill-rolling" tremor is consistent with Parkinson's disease. The characteristic pathological findings in Parkinson's disease include the presence of Lewy bodies, which are abnormal aggregates of protein, and a decrease in the number of pigmented neurons in the substantia nigra, a region of the brain involved in movement control. Therefore, examination of this patient's brain at autopsy would reveal Lewy bodies and decreased numbers of pigmented neurons in the substantia nigra.
10.
One of the more characteristic pathologic features of rheumatoid arthritis is
Correct Answer
D. Pannus formation
Explanation
Pannus formation is a characteristic pathologic feature of rheumatoid arthritis. Pannus refers to the abnormal tissue that forms in the synovial lining of joints affected by rheumatoid arthritis. This tissue is invasive and can erode cartilage and bone, leading to joint deformities and destruction. Pannus formation is a key factor in the progression of rheumatoid arthritis and contributes to the chronic inflammation and pain associated with the disease.
11.
An essential pathological feature of osteoarthritis is
Correct Answer
B. Degeneration of the articular cartilage
Explanation
Osteoarthritis is characterized by the degeneration of the articular cartilage, which is the smooth, protective covering on the ends of bones in a joint. This degeneration leads to joint pain, stiffness, and limited mobility. Widening of the joint space, "swan neck" deformity of the fingers, fibrous ankylosis, and calcification of the meniscus are not essential pathological features of osteoarthritis.
12.
A 55‑year‑old man has observed vague bony pains in the last few months and, more recently that his favorite hat no longer seems to fit. On examining him you observe that the skin over one of the painful bony areas is distinctly warm. At this point you are leaning towards a diagnosis of
Correct Answer
C. Paget's disease
Explanation
The symptoms described in the question, including vague bony pains and a change in the fit of a hat, along with the observation of warm skin over a painful bony area, are consistent with Paget's disease. Paget's disease is a chronic bone disorder characterized by abnormal bone remodeling, leading to enlarged and weakened bones. The warm skin over a painful bony area suggests increased blood flow and inflammation, which are common in Paget's disease. Mucopolysaccharidosis, osteomyelitis, osteopetrosis, and septic arthritis do not typically present with these specific symptoms.
13.
A known complication of avascular necrosis of bone is
Correct Answer
D. Secondary osteoarthritis
Explanation
Avascular necrosis of bone occurs when there is a loss of blood supply to the bone, leading to bone cell death. This can result in the collapse of the bone and subsequent development of secondary osteoarthritis. Secondary osteoarthritis refers to the degeneration of the joint surface due to an underlying condition or injury. In the case of avascular necrosis, the damage to the bone can cause abnormal stress on the joint, leading to the development of osteoarthritis. This is a known complication of avascular necrosis, making it the correct answer.
14.
A 19‑year‑old man has been observing increasing swelling of the right knee and the suddenly develops a fracture of the distal femur when coming down the steps of his house. An x‑ray suggests a mass arising from the femur and the radiologist thinks he sees a "Codman's" triangle. Even before you know the results of the biopsy, you strongly suspect
Correct Answer
C. Osteosarcoma
Explanation
The presence of a fracture along with a mass arising from the femur and the radiologist's observation of a "Codman's" triangle on the x-ray suggests a malignant bone tumor. Osteosarcoma is the most common primary malignant bone tumor in young adults and often presents with pain, swelling, and fractures. Fibrous dysplasia and Paget's disease are benign conditions that do not typically cause fractures. Chondrosarcoma is a malignant tumor of cartilage, which would not be consistent with the findings described. Non-ossifying fibroma is a benign bone lesion that does not typically cause fractures.
15.
A 68‑year‑old post‑menopausal woman has been experiencing pain in the upper portion of her back, development of "hump" back and her children tell her that she seems to be getting shorter. This condition might have been prevented had she taken:
Correct Answer
B. Hormone replacement therapy
Explanation
Hormone replacement therapy (HRT) could have potentially prevented the symptoms described in the question. The woman is experiencing pain in the upper portion of her back, which could be indicative of osteoporosis. HRT is known to help prevent bone loss and reduce the risk of fractures in post-menopausal women. The development of a "hump" back and a decrease in height are also common signs of osteoporosis. Therefore, if the woman had taken hormone replacement therapy, it could have potentially prevented or slowed down the progression of osteoporosis and its associated symptoms.
16.
One of the histopathological features of a typical fibrosarcoma is
Correct Answer
E. A herring bone pattern
Explanation
A herring bone pattern is a characteristic histopathological feature of a typical fibrosarcoma. This pattern refers to the arrangement of tumor cells in a parallel or perpendicular orientation, resembling the pattern of a herringbone. This arrangement is often seen in fibrosarcomas and helps in distinguishing them from other types of tumors. The herring bone pattern is formed due to the interlacing of spindle-shaped tumor cells, which gives a distinct appearance under a microscope.
17.
A 15‑year‑old boy complains of pain that appears to be coming from the middle of his right thigh. X‑ray studies confirm the presence of a lytic lesion measuring 0.8 cm. On further questioning, the boy says that the pain is relieved by aspirin. His mother is very anxious and fears that the lesion is malignant. However you assure her it is likely to be benign. You are thinking of
Correct Answer
A. Osteoid osteoma
Explanation
The presence of a lytic lesion and the relief of pain with aspirin are characteristic features of osteoid osteoma. Osteoid osteoma is a benign bone tumor that commonly affects young individuals and is often associated with nocturnal pain that is relieved by nonsteroidal anti-inflammatory drugs (NSAIDs) such as aspirin. Ewing's sarcoma is a malignant bone tumor that typically presents with pain and swelling but does not respond to NSAIDs. Pott's disease refers to tuberculosis of the spine and would not present with a lytic lesion in the thigh. Fibrous cortical defect is a benign lesion that typically does not cause pain. Chronic osteomyelitis is an infection of the bone that would not present as a lytic lesion.
18.
Bone tumors are generally named
Correct Answer
D. After the tissue they produce
Explanation
Bone tumors are generally named after the tissue they produce because it provides a clear indication of the type of tumor and its characteristics. This naming convention helps in identifying and classifying different types of bone tumors based on the specific tissue they originate from. It allows for better understanding and communication among medical professionals, facilitating proper diagnosis and treatment planning for patients with bone tumors.
19.
Your patient is a 15‑year‑old who presented in nephrotic syndrome with hematuria and proteinuria. Biopsy reveals type II MPGN. Your patient's serum complement and immunoglobulin profile revealed:
Correct Answer
D. Decreased C3, normal C1 and C4
Explanation
The given answer suggests that the patient has decreased C3 levels, but normal C1 and C4 levels. This pattern is consistent with type II MPGN, which is characterized by immune complex deposition in the glomeruli. In type II MPGN, there is dysregulation of the alternative complement pathway, leading to decreased C3 levels. The normal C1 and C4 levels indicate that the classical complement pathway is not involved. This pattern of complement and immunoglobulin profile helps in confirming the diagnosis of type II MPGN.
20.
Your patient is diagnosed with Goodpasture syndrome. You know the immunofluorescent pattern on the renal biopsy will be __________, even before you go to confer with your renal pathologist
Correct Answer
A. Linear, continuous
Explanation
Patients with Goodpasture syndrome typically present with linear, continuous immunofluorescent pattern on renal biopsy. This pattern is characterized by linear deposition of immunoglobulin G (IgG) along the glomerular basement membrane. This finding is consistent with the pathophysiology of Goodpasture syndrome, which involves the formation of autoantibodies against the alpha-3 chain of type IV collagen in the basement membrane. The linear, continuous pattern is a key diagnostic feature of Goodpasture syndrome and helps differentiate it from other renal diseases with different immunofluorescent patterns.
21.
A patient with polycystic kidney disease also has hepatic fibrosis, portal hypertension and splenomegaly. You know that
Correct Answer
E. This patient inherited the polycystic kidney disease in an autosomal recessive manner
Explanation
The presence of hepatic fibrosis, portal hypertension, and splenomegaly in a patient with polycystic kidney disease suggests that the patient inherited the disease in an autosomal recessive manner. Autosomal recessive inheritance means that both copies of the gene responsible for the disease must be mutated in order for the disease to manifest. In this case, the patient likely received a mutated copy of the gene from both parents, leading to the development of polycystic kidney disease along with the associated complications.
22.
A 9‑year‑old begins to pass bright red blood in her urine about 3 weeks after a streptococcal infection. You immediately ask the nephrologist to perform a renal biopsy. You believe the immunofluorescence will demonstrate
Correct Answer
A. Granular deposits of C3, IgG and IgM in the glomeruli
Explanation
Based on the presentation of a 9-year-old with bright red blood in her urine after a streptococcal infection, the most likely diagnosis is post-streptococcal glomerulonephritis (PSGN). PSGN is characterized by immune complex deposition in the glomeruli, resulting in inflammation and damage to the kidneys. The immunofluorescence pattern seen in PSGN typically shows granular deposits of complement component C3, immunoglobulin G (IgG), and immunoglobulin M (IgM) in the glomeruli. This pattern is consistent with the immune response seen in PSGN and helps confirm the diagnosis.
23.
Your patient has been diagnosed with rapidly progressive glomerulonephitis, Type II. You know that
Correct Answer
B. Without your intervention, your patient will likely die within weeks to months
Explanation
The correct answer suggests that without immediate intervention, the patient diagnosed with rapidly progressive glomerulonephritis, Type II, is at high risk of death within a few weeks to months. This implies that prompt action is necessary to prevent a fatal outcome.
24.
A patient with Berger Disease will have
Correct Answer
B. Mesangial deposition of IgA within glomeruli
Explanation
Berger Disease, also known as IgA nephropathy, is characterized by the deposition of IgA antibodies in the mesangium of the glomeruli. This deposition leads to inflammation and damage to the kidneys. The elevation of serum C3, C4, and C1 is not typically seen in Berger Disease. IgG and anti GBM antibodies are not associated with this condition. Massive, diffuse crescent formation within the renal corpuscles is not a characteristic feature of Berger Disease. Antibodies to Shiga protein are not typically deposited in the glomeruli in this condition. Therefore, the correct answer is the mesangial deposition of IgA within the glomeruli.
25.
You have a diabetic patient who is presently in renal failure. You suspect if you were to biopsy his kidneys, you would see the pathognomonic lesion for diabetes mellitus which is
Correct Answer
B. Nodular glomerulosclerosis
Explanation
Nodular glomerulosclerosis is the pathognomonic lesion for diabetes mellitus. It is characterized by the presence of nodules or Kimmelstiel-Wilson lesions in the glomeruli of the kidneys. These nodules are composed of thickened basement membranes and an accumulation of extracellular matrix material. This lesion is specific to diabetes mellitus and is not commonly seen in other renal diseases. Other options such as arteriolonephrosclerosis, wire loop lesion of the glomerulus, diffuse glomerulosclerosis, and crescentic glomerulonephritis are not specific to diabetes mellitus and are seen in other renal conditions.