Examkin

Soru

Zorluk: OrtaPhysical Examination Findings

A 58-year-old male is evaluated in the ambulatory neurology clinic for progressive walking difficulty, which he notes is severely exacerbated in dimly lit environments. Over the past six months, he has also experienced sudden, intense, "electric shock-like" pains shooting down both legs. His medical history is notable only for a painless genital sore in his twenties that healed spontaneously without treatment. On examination, he demonstrates a wide-based, stomping gait. When instructed to stand with his feet approximated and arms outstretched, he remains stable with his eyes open; however, upon closing his eyes, he sways dramatically and requires assistance to prevent a fall. Deep tendon reflexes cannot be elicited at the knees or ankles. Perception of tuning fork vibration and joint position is profoundly impaired in the distal lower extremities. Muscle strength is graded as 5/55/5 globally.

Further physical examination of this patient's eyes is most likely to reveal which of the following pupillary abnormalities?

  1. Bilaterally small, irregular pupils that constrict to near targets but do not react to direct lightCevap
  2. B
    A unilaterally dilated pupil that is sluggishly reactive to light and exhibits delayed redilation
  3. C
    Paradoxical dilation of one pupil when a light source is rapidly moved from the contralateral eye
  4. D
    A unilateral small pupil with a mild droop of the ipsilateral upper eyelid
  5. E
    Bilaterally dilated pupils that are entirely unreactive to both light and near vision

Cevap

The patient most likely has bilaterally small, irregular pupils that constrict to near targets but do not react to direct light (Argyll Robertson pupils).
The correct answer describes Argyll Robertson pupils, which are highly specific for neurosyphilis. The patient's clinical presentation—sensory ataxia (manifested by falls in the dark and a positive Romberg sign), absent lower extremity reflexes, impaired proprioception, and lancinating 'lightning' pains—is the classic tetrad of tabes dorsalis. This is a form of tertiary neurosyphilis caused by Treponema pallidum infection that preferentially damages the dorsal columns and dorsal roots of the spinal cord. The history of a painless genital ulcer decades prior is pathognomonic for a primary syphilitic chancre. Argyll Robertson pupils are bilaterally small and accommodate (constrict to near vision) but do not react to direct light due to bilateral lesions in the pretectal nuclei.

Adım Adım Çözüm

1
Analyze the gait and sensory findings
The patient has a positive Romberg sign, impaired proprioception/vibration, and a wide-based gait, indicating sensory ataxia localizing to the dorsal columns.
Differentiating sensory ataxia from cerebellar ataxia is critical; a positive Romberg sign confirms a proprioceptive, rather than cerebellar, deficit.
2
Integrate the reflex findings and pain history
Absent lower extremity reflexes and 'electric shock-like' (lightning) pains indicate involvement of the dorsal nerve roots.
The combination of dorsal column and dorsal root degeneration is the pathologic hallmark of tabes dorsalis.
3
Correlate with the patient's medical history
The history of a spontaneously healing, painless genital sore decades ago strongly suggests an untreated primary syphilis infection (chancre).
Tertiary neurosyphilis often presents decades after the primary infection.
4
Identify the expected associated physical exam finding
Tabes dorsalis is classically associated with Argyll Robertson pupils, which exhibit light-near dissociation.
Identifying the eponymous pupillary sign solidifies the clinical diagnosis of neurosyphilis.

Anahtar Kavram

Tabes dorsalis (tertiary neurosyphilis) presents with posterior column degeneration (sensory ataxia, positive Romberg sign) and dorsal root damage (areflexia, lightning pains), and is classically associated with Argyll Robertson pupils (light-near dissociation).
Bu soruyu puanla

Konular

Physical Examination Findings

Bu konudan daha fazla soru