What is the diagnosis for a person presenting with unspecified symptoms?

Diagnostic Approach to Unspecified Symptoms

When a person presents with unspecified symptoms, the fundamental principle is that no diagnosis should be labeled as "unexplained" or "idiopathic" until a thorough, systematic evaluation has excluded all common and uncommon causes—premature closure on an "unexplained" diagnosis represents inadequate workup rather than a true diagnostic entity. 1

Critical Framework for Evaluation

The approach must be methodical and exhaustive before concluding symptoms are unexplained:

Initial Diagnostic Priorities

Complete the full diagnostic workup for common causes first. The American College of Chest Physicians emphasizes that unexplained diagnoses are made far too often based on inadequate evaluation 1. Common pitfalls include:

• Failing to empirically treat suspected conditions even when classic findings are absent (e.g., treating upper airway cough syndrome despite lack of typical signs) 1
• Omitting appropriate imaging when clinically indicated (e.g., sinus imaging for occult sinusitis) 1
• Not performing specialized testing such as bronchoprovocation challenges or adequate empiric trials for conditions like cough-variant asthma 1
• Inadequately evaluating conditions that may lack typical symptoms, particularly gastroesophageal reflux disease when GI symptoms are absent 1

Systematic Exclusion of Uncommon Causes

Before accepting an "unexplained" label, actively search for rare or subtle diagnoses that are frequently missed 1:

• Occult heart failure 1
• Interstitial lung disease 1
• Neuromuscular disorders 1
• Subtle bronchiectasis 1
• Suppurative airway disease 1
• Thyroiditis 1
• Isolated endobronchial abnormalities 1

Specialized Diagnostic Considerations

If symptoms suggest specific organ system involvement, apply disease-specific diagnostic algorithms:

For Suspected Pulmonary Fibrosis

• Classify as fibrotic versus nonfibrotic based on high-resolution CT findings (reticular abnormality, ground-glass opacity with traction bronchiectasis, honeycombing, loss of lobar volume) 1
• Exclude hypersensitivity pneumonitis through comprehensive environmental and occupational questionnaires tailored to geographic region 1
• Continue exposure history gathering until diagnosis or exclusion is certain 1

For Suspected Inflammatory Bowel Disease

• When clinical, endoscopic, and histologic data are insufficient to distinguish between ulcerative colitis and Crohn's disease, use the term "inflammatory bowel disease unclassified" rather than "indeterminate colitis" 1
• Perform ileocolonoscopy combined with CT enterography for comprehensive small bowel assessment 1
• Consider video capsule endoscopy for small bowel pathology when standard endoscopy is non-diagnostic 1

For Chronic Multisymptom Illness

Build and maintain a therapeutic alliance while conducting thorough symptom evaluation and assessing for comorbid conditions 1. The VA/DoD guidelines emphasize:

• Evaluate whether symptoms meet criteria for chronic multisymptom illness (CMI) 1
• Assess if CMI coexists with another diagnosis that may partially contribute to symptoms 1
• Provide patient education on findings and develop individualized treatment plans based on patient needs, goals, and preferences 1

Temporal and Contextual Factors

Consider the timing and evolution of symptoms:

• For head trauma with unexplained neurologic deficits, recognize that 17-36% of cerebrovascular injuries develop symptoms >24 hours after injury 1
• Document whether symptoms are acute, subacute, or chronic, as this influences differential diagnosis 1
• Assess for disease progression despite apparent management, suggesting unrecognized exposures or contributing factors 1

Documentation Requirements

When capacity to make medical decisions is in question, document:

• Capacity is decision-specific and must be assessed without preconceptions 2
• An unwise decision is not evidence of lack of capacity 2
• Detailed assessment should be reserved for situations requiring major decisions when time permits 2

When "Unexplained" May Be Appropriate

Only after exhaustive evaluation should "unexplained" terminology be considered. The American College of Chest Physicians unanimously recommends using "unexplained" rather than "idiopathic" for the small subset of patients where no usual explanation exists despite complete workup 1. However, this represents a minority of cases—studies showing 0% unexplained diagnoses demonstrate that thorough evaluation typically identifies causation 1.

The key principle: diagnostic uncertainty reflects inadequate investigation until proven otherwise through systematic, comprehensive evaluation.