KMU Past Paper Practice

Question:
A 9-year-old girl has localized tibial pain for three weeks with minimal fever. Imaging demonstrates a small, well-circumscribed intraosseous lesion surrounded by sclerosis. Which classification best describes this infection?

Options:

Explanation:
An indolent, localized intraosseous lesion surrounded by reactive sclerosis is characteristic of subacute osteomyelitis, commonly presenting as a Brodie abscess.

Question:
A neonate develops fever, irritability and swelling over the femur following a bloodstream infection. Which organism group is particularly important in this age group?

Options:

Explanation:
Group B streptococci and enteric gram-negative bacilli are important causes of neonatal hematogenous osteomyelitis.

Question:
An incompletely immunized 3-year-old child presents with fever and acute pain over the humerus. Which organism should be considered in addition to Staphylococcus aureus?

Options:

Explanation:
Haemophilus influenzae is an important consideration in incompletely immunized young children with invasive bone infection.

Question:
A young man steps on a nail that penetrates through the sole of his shoe. Several days later, he develops infection involving a metatarsal. Which organism is particularly associated with this setting?

Options:

Explanation:
Pseudomonas is classically associated with osteomyelitis following a penetrating plantar injury, particularly through footwear.

Question:
In a child with acute osteomyelitis, purulent material spreads from the medullary cavity through the cortex and collects beneath the periosteum. Which age-related feature facilitates this collection?

Options:

Explanation:
The periosteum is relatively loosely attached in children, allowing pus to lift it from the cortex and form a subperiosteal abscess.

Question:
Gross examination of bone from a patient with rapidly progressive infection shows congested marrow containing yellow-white material. Which pathological process produced this appearance?

Options:

Explanation:
Acute pyogenic osteomyelitis produces neutrophil-rich exudate and pus within congested, edematous marrow spaces.

Question:
Histology from an early bone infection shows numerous neutrophils, marrow-cell necrosis and small bacterial colonies. Which stage of disease is represented?

Options:

Explanation:
Neutrophilic inflammation, bacterial colonies and acute marrow necrosis are characteristic microscopic findings in acute pyogenic disease.

Question:
An immunocompromised patient has slowly progressive vertebral pain with little systemic toxicity. Biopsy shows a granulomatous inflammatory pattern rather than abundant neutrophils. Which etiological category is most likely?

Options:

Explanation:
Mycobacteria and fungi commonly produce a more indolent, granulomatous form of osteomyelitis, especially in immunocompromised patients.

Question:
A patient with acute osteomyelitis develops increasing swelling after pus passes through cortical vascular channels. Which lesion is expected to form next?

Options:

Explanation:
Purulent material may traverse cortical channels and collect beneath the periosteum, producing a subperiosteal abscess.

Question:
A bone specimen from a long-standing infection contains lymphocytes, plasma cells, macrophages, fibrosis and areas of newly deposited woven bone. What do these findings indicate?

Options:

Explanation:
Chronic inflammatory cells and fibrosis indicate persistent infection, while woven bone reflects an ongoing reparative response.

Question:
A child with acute bone infection complains of severe pain before marked external swelling becomes visible. Which pathological change most directly explains the early intensity of pain?

Options:

Explanation:
Purulent exudate increases intraosseous pressure and irritates pain-sensitive periosteal structures, producing severe focal pain.

Question:
A febrile child with suspected hematogenous osteomyelitis is assessed before antimicrobial treatment. Which investigation may directly identify the organism without sampling the bone?

Options:

Explanation:
Blood cultures may identify the causative organism in acute hematogenous osteomyelitis because the infection follows bacteremia.

Question:
A patient with localized bone pain has elevated inflammatory markers. Which interpretation of this finding is most appropriate?

Options:

Explanation:
Raised inflammatory markers support active inflammation and help monitor response, but they cannot independently establish the diagnosis or organism.

Question:
Imaging in a patient with long-standing bone infection shows marked cortical thickening and irregular sclerosis. Which pathological response best accounts for these findings?

Options:

Explanation:
Surviving periosteal and endosteal osteogenic cells deposit irregular reactive bone, producing sclerosis and cortical thickening.

Question:
A patient with chronic osteomyelitis develops recurrent fever and positive blood cultures during an acute exacerbation. Which complication has occurred?

Options:

Explanation:
Entry of organisms from the infected bone into the circulation causes bacteremia and may progress to sepsis or distant metastatic infection.

Question:
A patient with chronic tibial osteomyelitis develops progressive deformity and reduced limb function despite control of systemic infection. Which process best explains this disability?

Options:

Explanation:
Recurrent inflammation, fibrosis, bone loss and disorganized reactive bone distort architecture and produce chronic functional impairment.

Question:
An orthopedic unit seeks to reduce postoperative bone infections. Which measure acts most directly at the stage of microbial introduction during surgery?

Options:

Explanation:
Aseptic technique reduces direct implantation of microorganisms during orthopedic procedures and implant placement.

Question:
A diabetic patient with peripheral vascular insufficiency has recurrent osteomyelitis beneath a foot ulcer. Which factor most directly reduces both immune defense and tissue repair?

Options:

Explanation:
Poor perfusion limits oxygen delivery, leukocyte access, antimicrobial penetration and wound healing, promoting persistent infection.

Question:
A pathologist examines an irregular opening within reactive cortical bone that communicates with a draining sinus. What is the functional significance of this opening?

Options:

Explanation:
An opening in reactive new bone allows pus to pass from the deep infected focus toward a sinus tract and the skin surface.

Question:
A patient with a history of treated bone infection has no fever but continues to experience localized pain and intermittent swelling. Imaging shows fibrosis, cortical thickening and irregular reactive bone. Which interpretation is most appropriate?

Options:

Explanation:
Fibrosis, cortical thickening and irregular reactive bone indicate chronic osteomyelitis with continuing architectural distortion despite limited systemic symptoms.