Category: General Medicine

Pyrexia of Unknown Origin ( Part -1 )

Dr.Urusa Inamdar1 Comment 
Written by - Dr.Urusa I Inamdar

Definition:

  1. Fever higher than 38.3 c ( 101F ) on several occasions.
  2. Illness of more than 3 weeks duration.
  3. No diagnosis made after 1 week of inpatient investigation.

Common causes not be missed for Fever which is not subsiding after 1 week of treatment:

  • enteric fever
  • Tuberculosis
  • viral fever
  • Leptospirosis
  • Scrub typhus
  • urinary tract infection
  • intraabdominal abscess
  • hepatitis A and B

Common etiologies of Fever of Unknown Origin

  • Infections
  1. Miliary TB
  2. Enteric Fever
  3. Intraabdominal abscess
  4. TB meningitis
  5. Brucellosis
  6. EBV/CMV
  7. Complicated UTI
  • Neoplastic disorders
  1. Lymphoma
  2. Hepatoma/Liver metastasis
  3. Colon cancer
  4. Myeloproliferative disorders
  5. Renal cell carcinoma
  6. CNS tumors
  • Rheumatic /inflammatory disorders
  1. Still’s disease
  2. Temporal arteritis
  3. Rheumatic arthritis
  4. SLE
  5. Sarcoidosis
  6. Polyarticular gout
  7. Polymyalgia rheumatica
  • Miscellaneous
  1. Drug fever
  2. Alcoholic cirrhosis
  3. Sub-acue thyroiditis
  4. PTE
  5. Inflammatory bowel disease

Classification of Fever of Unknown Origin

  • Classic

duration of more than 3 weeks.

Evaluation of atleast 3 outpatient visits or 3 days on hospital.

  1. Infection
  2. Malignancy
  3. Collagen vascular disease
  • Nosocomial

patient hospitalized more than 24 hrs but no fever or incubating on admission.

Evaluation of atleast 3 days.

  1. Clostridium difficile enterocolitis
  2. Drug induced
  3. Pulmonary embolism
  4. Septic thrombophlebitis
  • Immune deficient

Neutrophil count less than 500 per mm3.

Evaluation of atleast 3 days.

  1. Opportunistic bacterial infection
  2. Aspergillosis, Candidiasis, Toxoplasmosis
  3. Herpes virus
  • HIV associated

Duration of more than 4 weeks for outpatients.

More than 3 days for inpatient.

HIV infection confirmed.

  • Cytomegalovirus
  • Mycobacterium
  • PCP

Reference

  • Gsk – webevent console
  • Dental notes
  • Davidson’s – Principles and practice of Medicine

Clotting mechanism – Enzyme cascade theory

Charu LataLeave a comment

Clotting – It is defined as the process in which blood looses it’s fluidity and becomes a jelly like substance few minutes after it is shed out.

Sequence of clotting mechanism – Enzyme cascade theory:

Cascade is a process that occurs through a series of steps , each step initiating the next until the final step is reached.

Stages of blood clotting :

  • Formation of prothrombin activator
  • Conversion of prothrombin into thrombin
  • Conversion of fibrinogen into fibrin

Sources – Sembulingam (Textbook of physiology)

Image source – Google images

SYNCOPE

Dr.MehnazLeave a comment
Transient loss of consciousness due to decreased cerebral perfusion

Vasovagal Syncope

Common faint
🔹Predisposing factors:
  • Hot/crowded enviornment
  • Fatique
  • Pain
  • Prolonged standing
  • Hunger, emotional
🔹Pathophysiology:

Prolonged standing

⬇️

⬇️ filling of Ventricle

⬇️

Venous pooling

⬇️

⬆️ sympathetic activation

⬇️

contraction of Ventricle

⬇️

Stimulation of Myocardial mechanoreceptors & vagal afferent fibers

⬇️

Vasodilation & Bradycardia

⬇️

Hypotension & Syncope

🔹Management:
Presyncope
•Stop the procedure
•Patient placed supine with legs slightly elevated
•Muscular movements, aids the return of blood from periphery
•If thought necessary, oxygen may be administered, using full-face mask or nasal hood.
•An ammonia ampule may be crushed and held under patient’s nose.
•Postponement of dental procedure.
Dr. Mehnaz Memon🖊

References: Practical medicine guide by PJ Mehta; Internet