Dandy-Walker syndrome

1) Disease Description (Causes and Symptoms)

• Definition: An acute viral disease caused by the Dengue virus, transmitted by Aedes mosquitoes (mainly Aedes aegypti and Aedes albopictus) in tropical and subtropical regions.
• Causes and pathophysiology:
  • There are four serotypes of the Dengue virus (the four major types). After infection with one serotype, reinfection with another serotype may increase the risk of developing severe disease (antibody-dependent enhancement).
  • The virus may affect peripheral blood and endothelial cells, causing fever, increased vascular permeability, a tendency to bleed, and abnormalities in blood coagulation.
• Main symptoms:
  • Fever (sudden high fever), severe headache (especially pain behind the eyes), muscle and joint pain (pain resembling bone pain), rash, loss of appetite, nausea/vomiting.
  • Mild signs of bleeding (nosebleeds, bleeding gums, petechiae on the skin, etc.) may occur.
  • In severe cases, increased vascular permeability may cause hypotension and shock (dengue shock syndrome), extensive bleeding (dengue hemorrhagic fever), and organ failure.

2) Treatment Methods

• General principles: As there is no specific antiviral drug, conservative (supportive) treatment based on symptoms is the main approach. It is important to recognize early warning signs and provide appropriate hospitalization, isolation, and treatment.
• Mild cases (outpatient care possible)
  • Get sufficient rest and maintain hydration (oral rehydration fluids). Use acetaminophen (such as Tylenol) for fever and pain.
  • Avoid nonsteroidal anti-inflammatory drugs (NSAIDs), aspirin, and similar medications because of the risk of bleeding.
  • Monitor body temperature and symptoms (vomiting, urine output, and presence of bleeding).
• Severe cases (hospitalization required)
  • Intravenous fluid therapy: Use an appropriate crystalloid solution (normal saline or Ringer's solution) according to the hemodynamic status; in cases of shock, provide rapid fluid replacement and monitoring (blood pressure, pulse, urine output, and blood tests).
  • If bleeding is severe, blood products (fresh frozen plasma, red blood cell transfusion, and, if necessary, platelet transfusion) are determined according to the bleeding status and test results. However, prophylactic platelet transfusion is not recommended (it may be considered in specific situations, such as clinically significant bleeding or a very low platelet count).
  • Oxygen therapy, intensive care (if necessary), and supportive treatment for related organ function (e.g., renal replacement therapy) may be provided.
• Medications
  • Fever and pain relief: Acetaminophen is recommended.
  • There are no antiviral drugs or specific treatments (treatment focuses on symptom management).
• Precautions (self-care)
  • Prevent dehydration (drink sufficient fluids) and monitor body temperature and signs of worsening symptoms (persistent vomiting, abdominal pain, bleeding, drowsiness/coma, etc.).
  • Do not use NSAIDs or aspirin at home.
  • Because worsening (increased vascular permeability) may occur mainly 3–7 days after infection, visit a medical institution immediately if symptoms worsen during this period.
• Prognosis
  • Most people recover from mild disease, but severe hemorrhagic or shock forms carry a high risk of death without appropriate treatment. Early recognition and fluid therapy greatly reduce the mortality rate.

3) Checkpoints Before an Outpatient Visit (Including Preparation and Example Questions)

• Items to prepare (bring to the hospital)
  • A list of medications currently being taken (including prescription and OTC medications), and information about allergies and underlying conditions (especially liver, heart, and kidney disease, and whether anticoagulants are being taken).
  • Recent body temperature records, the date symptoms began (such as the first day of fever), and records of vomiting, urine output, and signs of bleeding.
  • Previous test results (if available), such as a CBC and liver function tests.
• Key items medical staff will check during an outpatient visit
  • The date the fever began and the course of symptoms (especially the risk of worsening on days 3–7), presence or absence of signs of bleeding, changes in urine output, and changes in consciousness.
• Symptoms requiring emergency care (visit the emergency room immediately)
  • Persistent and severe abdominal pain/abdominal tenderness, repeated vomiting (unable to drink fluids), rapid pulse, low blood pressure, cold hands and feet, severe drowsiness/confusion, or active bleeding (vomiting blood, black stools, heavy nosebleeds, etc.).

4) General Example Questions to Ask the Doctor

• "Do I need to be hospitalized in my current condition? What symptoms should I watch for?"
• "What should I do if I am taking medications such as blood pressure medication or anticoagulants?"
• "Which medication can I take for fever and pain, and when and for how long may I take it?"
• "According to what criteria are the results of blood tests (such as platelet count and hematocrit) evaluated?"
• "For how many days after discharge should I limit activities such as exercise and returning to work?"

5) Examples of Disease-Specific Questions

• "I have had dengue fever before. Is the risk of progressing to severe disease higher if I become reinfected?"
• "When will the NS1/IgM test results be available, and what additional tests are needed if the initial test is negative?"