Chronic fatigue (outpatient symptom triage)
Phase C shard-3-neuro-sym wave-14 (2026-05-14) — symptom-workup template clones from symptom.constipation.v1 (wave-11), symptom.fuo.v1, symptom.anemia-workup.v1. Engine scope: chronic fatigue (≥6 mo) outpatient triage + cause stratification + screening workup + dispositional routing to disease-specific engines. ME/CFS IOM 2015 criteria evaluated when other causes excluded. Phenotypes covered (≥8): sleep_disorders_osa_narcolepsy_rls (~20-30%), depression_anxiety_psychiatric (~20%), anemia_anchored (~10-15%), hypothyroid_screen, hyperthyroid_screen, dm_uncontrolled, ckd_uremic, chf_low_output, chronic_infection_hiv_hcv_tb, malignancy_paraneoplastic, me_cfs_iom_2015, fibromyalgia_overlap, postviral_post_covid_long_covid, medication_induced, deconditioning_lifestyle, adrenal_insufficiency, rheumatologic_inflammatory, b12_folate_deficiency. Bayesian linkage (LR+, LR−, pre-test priors by age/sex, IOM 2015 ME/CFS thresholds, T_treat) lives in companion depth bundle _briefs/symptom.fatigue.v1.depth.md. 5 sibling differentiation rows: symptom.anemia-workup + psych.depression + endo.dm2 + id.covid19 + geriatrics.frailty-polypharmacy (all confirmed in ALL_DOSSIERS). 10 severity_triggers: severe_depression_si, osa_high_risk, me_cfs_iom_2015, long_covid_chronic, hiv_positive, hcv_chronic, severe_thyrotoxicosis, cardiac_low_output_hf, severe_anemia, geriatric_frailty. KEY SAFETY RULES: PHQ-9 ≥20 + SI → ED for psychiatric eval + safety plan; ME/CFS uses pacing NOT graded exercise therapy (IOM 2015 / CDC PMID 26561523 verify); modafinil ONLY for narcolepsy / OSA residual sleepiness (AVOID off-label for ME/CFS / depression); CPAP for OSA confirmed by polysomnography; universal HIV + HCV screening; B12 / iron repletion when deficient. Calculators wired (0): schema-blocked — calc.stop_bang, calc.epworth, calc.iom_me_cfs_criteria, calc.fibromyalgia_acr_2016, calc.phq9, calc.gds. Ticketed in shard-3 state file. Panels wired: panel.cbc + panel.renal + panel.lft + panel.thyroid + panel.inflammation + panel.iron + panel.lipid. Schema-blocked: workup.chronic_fatigue — NOT in clinical-tools-registry; manual application in setting playbook required_assessments. Regimen_axes intentionally empty — engine is triage-only. Stepwise pharmacologic ladder lives in setting_playbooks.outpatient.drug_actions. Setting playbook: single outpatient (per chronic engine convention) — ED triage and inpatient via escalation_triggers when needed (severe depression with SI, severe thyrotoxicosis, DKA, severe anemia with instability, etc.). SCAFFOLDED status: no workup.chronic_fatigue in clinical-tools-registry; PRODUCTION audit would fail. Will promote once registry entries land.
Entry points (18)
- symptomChronic fatigue + snoring + witnessed apnea + daytime sleepiness + obesity (STOP-BANG ≥3) — OSA screen; route to polysomnography; consider narcolepsy (cataplexy, hypnagogic hallucinations), RLS, periodic limb movement disordersleep_disorders_osa_narcolepsy_rls_screen
- symptomChronic fatigue + anhedonia + depressed mood + sleep disturbance + appetite change + concentration problems + PHQ-9 ≥10 — depression; route psych.depression.core.v1; comorbid anxiety / substance use commondepression_anxiety_psychiatric_anchored
- symptomChronic fatigue + pallor + dyspnea on exertion + Hb <12 (women) / <13 (men) — anemia workup; route symptom.anemia-workup.v1; iron-deficiency most common causeanemia_anchored_fatigue
- symptomChronic fatigue + cold intolerance + weight gain + constipation + bradycardia + elevated TSH — hypothyroidism; levothyroxine; if severe with myxedema → EDhypothyroid_screen_fatigue
- symptomChronic fatigue + heat intolerance + tachycardia + tremor + weight loss + suppressed TSH — hyperthyroidism; methimazole; if severe → route endo.thyroid-storm.core.v1hyperthyroid_screen_fatigue
- symptomChronic fatigue + polyuria + polydipsia + glucose >200 + HbA1c >6.5% — uncontrolled DM; route endo.dm2.core.v1; fatigue from chronic hyperglycemia + osmotic diuresisdm_uncontrolled_fatigue
- symptomChronic fatigue + eGFR <30 + uremic features (anorexia, pruritus, restless legs, sleep disturbance) — uremic fatigue; route neph.ckd.core.v1; renal anemia, secondary hyperPTH, sleep disorders contributeckd_uremic_fatigue
- symptomChronic fatigue + dyspnea + orthopnea + reduced EF + LE edema — low-output HF / HFrEF; route cardio.hfref.core.v1; GDMT optimization; fatigue is class III-IV symptomchf_low_output_fatigue
- symptomChronic fatigue + risk factors (sexual, IDU, transfusion, endemic exposure) + lymphadenopathy + B-symptoms — HIV / HCV / TB / EBV reactivation; route id.hiv-initial.chronic.v1 or id.hcv-initial.chronic.v1chronic_infection_hiv_hcv_tb_fatigue
- symptomChronic fatigue + WL + B-symptoms + lymphadenopathy + new mass / pain — malignancy / paraneoplastic; CT C/A/P + age-appropriate cancer screenmalignancy_paraneoplastic_fatigue
- symptomChronic fatigue ≥6 mo + post-exertional malaise + unrefreshing sleep + cognitive impairment OR orthostatic intolerance + substantial functional decline — ME/CFS per IOM 2015 (PMID 25695122 — verify); diagnosis of exclusion + symptom criteriame_cfs_iom_2015_criteria
- symptomChronic fatigue + widespread pain >3 mo + multiple tender points + cognitive symptoms + sleep disturbance — fibromyalgia (ACR 2016 criteria); duloxetine / pregabalin / SNRI; aerobic exercise; CBTfibromyalgia_overlap_fatigue
- symptomChronic fatigue + cognitive / autonomic / cardiopulmonary symptoms ≥3 mo after acute COVID — post-COVID / long COVID; route id.covid19.core.v1; multidisciplinary carepostviral_post_covid_long_covid
- symptomChronic fatigue + medication review reveals β-blocker / antihistamine / benzodiazepine / opioid / antidepressant / statin / antipsychotic / antiepileptic — drug-induced; deprescribe or substitute when feasiblemedication_induced_fatigue
- symptomChronic fatigue + sedentary lifestyle + poor sleep hygiene + caffeine excess + alcohol use + low physical activity — deconditioning / lifestyle; graded exercise + sleep hygiene + nutritional counselingdeconditioning_lifestyle_factors
- symptomChronic fatigue + orthostasis + hyperpigmentation + hyponatremia + hyperkalemia + nausea + WL — adrenal insufficiency (Addison); morning cortisol + ACTH; replacement therapyadrenal_insufficiency_fatigue
- symptomChronic fatigue + arthralgia + morning stiffness + serositis + rash + Raynaud + elevated CRP/ESR — rheumatologic (RA, SLE, vasculitis, PMR, Sjögren); ANA / RF / anti-CCP / ANCArheumatologic_inflammatory_fatigue
- symptomChronic fatigue + cognitive symptoms + paresthesias + macrocytic anemia + low B12 (<200 pg/mL) — B12 deficiency (NEJM 2013 PMID 22106456); folate; check intrinsic factor antibodies (pernicious anemia)b12_folate_deficiency_fatigue
Required inputs (39)
- agerequireddemographic • used at CONTEXTAge shifts priors: young adult → depression / chronic infection / ME/CFS / postviral; middle-age → depression / hypothyroid / DM / chronic disease; elderly → hypothyroid / cardiac / renal / depression / geriatric frailty / medication-induced (Mark 2011 PMID 19490842 — verify)
- sexrequireddemographic • used at CONTEXTSex shifts priors: female > male for hypothyroid, anemia, fibromyalgia, ME/CFS, depression, autoimmune; male > female for OSA (overlap with obesity), HCV / IDU history
- duration_and_pattern_of_fatiguerequiredsymptom • used at FRAMEChronic fatigue defined as ≥6 mo (IOM 2015 — verify); pattern: post-exertional malaise (ME/CFS), morning > evening (hypothyroid), evening > morning (depression), exercise-induced (cardiac low-output)
- functional_impact_substantial_declinerequiredsymptom • used at FRAMESubstantial functional decline (≥50% from baseline) part of IOM 2015 ME/CFS criteria; differentiates clinical fatigue from "tired" complaint; quality-of-life measures
- post_exertional_malaiserequiredsymptom • used at ENTRYPEM (worsening of symptoms 24-48 h after physical / cognitive / emotional exertion) — hallmark of ME/CFS per IOM 2015 (PMID 25695122); not typical in depression / deconditioning
- unrefreshing_sleep_or_sleep_disturbancerequiredsymptom • used at ENTRYUnrefreshing sleep (sleep without restoration) — IOM 2015 ME/CFS criterion; also seen in OSA, depression, RLS, fibromyalgia, chronic pain
- cognitive_brain_fog_concentrationrequiredsymptom • used at ENTRYCognitive impairment (brain fog, decreased concentration, memory) — IOM 2015 ME/CFS; also in depression, hypothyroid, B12 deficiency, OSA, long COVID
- orthostatic_intolerancesymptom • used at ENTRYOrthostatic intolerance (POTS, neurally mediated hypotension) — alternative IOM 2015 ME/CFS criterion to cognitive impairment; also adrenal insufficiency, autonomic neuropathy
- mood_anhedonia_psych_featuresrequiredsymptom • used at ENTRYPHQ-9 ≥10 + anhedonia + sleep / energy disturbance → depression (most common cause of chronic fatigue in primary care; route psych.depression.core.v1)
- sleep_quality_snoring_witnessed_apnea_stop_bangrequiredsymptom • used at CONTEXTSTOP-BANG screen (snoring, tired, observed apnea, BP, BMI >35, age >50, neck >40 cm, male sex) → ≥3 OSA likely; polysomnography referral
- weight_change_appetite_temp_intolerancerequiredsymptom • used at CONTEXTWL → malignancy / hyperthyroid / DM / depression; weight gain → hypothyroid / depression with carb craving; cold intolerance → hypothyroid; heat intolerance → hyperthyroid
- pain_widespread_arthralgiasymptom • used at ENTRYWidespread pain → fibromyalgia (ACR 2016); arthralgia + morning stiffness → RA / SLE / vasculitis; muscle pain → statin / hypothyroid / rheumatologic
- medication_review_beta_blocker_antihistamine_bzd_opioid_antidepressantrequiredhistory • used at CONTEXTβ-blocker, antihistamine (especially first-gen), BZD, opioid, antidepressant (mirtazapine, TCA), statin (rare myalgia), antipsychotic, antiepileptic — drug-induced fatigue; deprescribe or substitute
- chronic_disease_history_dm_ckd_hf_copd_cancerrequiredhistory • used at CONTEXTDM (chronic hyperglycemia), CKD (uremia, anemia, secondary hyperPTH), HF (low cardiac output), COPD (hypoxia), cancer (paraneoplastic, treatment-related); each routes to disease-specific engine
- infection_history_hiv_hcv_tb_ebv_lymerequiredhistory • used at CONTEXTHIV (universal screen); HCV (IDU, transfusion); TB (endemic, contact); EBV reactivation; Lyme (endemic, tick exposure); each routes to disease-specific engine
- recent_acute_illness_postviral_post_covidrequiredhistory • used at CONTEXTPost-viral fatigue / post-COVID / long COVID (≥3 mo after acute COVID) — common cause of chronic fatigue post-2020; route id.covid19.core.v1; multidisciplinary care
- lifestyle_caffeine_alcohol_exercise_sleep_hygienehistory • used at CONTEXTLifestyle factors: caffeine excess, alcohol use, sedentary lifestyle, poor sleep hygiene, screen time, shift work — modifiable; deconditioning common
- rheumatologic_family_autoimmune_historyhistory • used at CONTEXTFamily hx autoimmune (RA, SLE, MS, thyroid); personal hx Raynaud, sicca symptoms; rheumatologic workup if elevated CRP/ESR + features
- red_flags_neuro_cardiac_severe_systemicrequiredsymptom • used at RED_FLAGSRed flags: new focal neuro deficit, severe chest pain, syncope, severe weight loss >10%, hemoptysis, painless lymphadenopathy >2 cm, severe SOB → ED workup
- cbc_with_diffrequiredlab • used at INITIAL_WORKUPAnemia (most common: iron-deficiency → symptom.anemia-workup; macrocytic → B12/folate; pancytopenia → marrow / lymphoma); leukocytosis (chronic infection); lymphocytosis (lymphoma, EBV)
- bmp_glucose_electrolytesrequiredlab • used at INITIAL_WORKUPGlucose / HbA1c (DM); BUN/Cr (CKD); Na (SIADH, Addison); K (Addison); Ca (hyperPTH); fasting glucose if non-diabetic
- lft_albuminrequiredlab • used at INITIAL_WORKUPLFT (hepatic disease, alcohol, drug-induced, HCV); albumin (chronic disease, nutrition); hepatitis screen if elevated
- tsh_t4_freerequiredlab • used at INITIAL_WORKUPTSH (elevated → hypothyroid; suppressed → hyperthyroid); first-line endocrine workup; reflex T4/T3 if abnormal
- hba1c_fasting_glucoserequiredlab • used at INITIAL_WORKUPHbA1c ≥6.5% / fasting glucose ≥126 → DM screen; route endo.dm2.core.v1; pre-diabetic counseling if 5.7-6.4%
- b12_folate_iron_studiesrequiredlab • used at INITIAL_WORKUPB12 <200 → deficiency (route symptom.anemia-workup if MCV high); folate; iron studies (ferritin <30 → iron-deficiency; transferrin saturation)
- crp_esr_inflammationrequiredlab • used at INITIAL_WORKUPCRP / ESR — inflammatory screen; elevated → rheumatologic / chronic infection / malignancy; ESR >100 nonspecific concerning marker
- hiv_universal_screenrequiredlab • used at INITIAL_WORKUPUniversal HIV screen (CDC, USPSTF); HCV screen (USPSTF universal adults); syphilis if risk factors
- urinalysisrequiredlab • used at INITIAL_WORKUPUA — proteinuria (CKD); glucose (DM); hematuria (renal disease)
- phq9_geriatric_depression_scalerequiredlab • used at CONTEXTPHQ-9 ≥10 → depression; GDS for ≥65; PHQ-9 ≥20 → severe depression with suicide risk screen (PHQ-9 item 9)
- stop_bang_questionnairelab • used at CONTEXTSTOP-BANG ≥3 → OSA likely; polysomnography referral; ≥5 → high-risk OSA
- cortisol_acth_morninglab • used at BRANCHING_WORKUPAdrenal insufficiency screen — morning cortisol <5 µg/dL + ACTH > 100 → Addison; orthostasis + hyperpigmentation + hyponatremia clinical features
- ana_rf_anti_ccp_anca_if_rheum_featureslab • used at BRANCHING_WORKUPRheumatologic workup if arthralgia + morning stiffness + elevated CRP/ESR + features (Raynaud, sicca, rash); route to rheumatology if positive
- hcv_screen_universalrequiredlab • used at INITIAL_WORKUPHCV universal adult screening (USPSTF); IDU / transfusion history; chronic fatigue is common HCV presentation; route id.hcv-initial.chronic.v1
- tb_igra_if_endemiclab • used at BRANCHING_WORKUPTB IGRA if endemic exposure / chronic cough / WL / B-symptoms; latent vs active workup
- lyme_serology_if_endemic_tick_exposurelab • used at BRANCHING_WORKUPLyme serology if endemic exposure + tick history + erythema migrans / arthralgia / cognitive symptoms; chronic Lyme is controversial
- epworth_sleepiness_scalelab • used at CONTEXTEpworth >10 → excessive daytime sleepiness; combined with STOP-BANG for OSA / narcolepsy screening
- cxr_if_pulmonary_featuresimaging • used at INITIAL_WORKUPCXR — interstitial disease, TB, malignancy, HF (cardiomegaly, congestion); first-line lung screen
- echocardiogram_if_cardiac_featuresimaging • used at BRANCHING_WORKUPTTE — reduced EF (cardiac low-output); valvular disease; diastolic dysfunction; pericardial effusion; route cardio.hfref.core.v1 if EF <40%
- polysomnography_if_stop_bang_highimaging • used at BRANCHING_WORKUPPolysomnography — confirm OSA (AHI ≥5 mild, ≥15 moderate, ≥30 severe); narcolepsy (MSLT); RLS / PLMD evaluation
12-phase flow (12)
- 1FRAMEDocument chronic fatigue ≥6 mo (IOM 2015 criteria for ME/CFS); substantial functional decline (≥50% from baseline); rule out acute / subacute fatigue (<6 mo); calibrate baseline activity / quality-of-lifeinputs: duration_and_pattern_of_fatigue, functional_impact_substantial_declineadvance: Chronic ≥6 mo + functional decline documented
- 2ENTRYPhenotype-defining features: PEM (post-exertional malaise — ME/CFS signature), unrefreshing sleep, cognitive impairment, orthostatic intolerance, mood, pain, sleep quality — anchor entry phenotypeinputs: post_exertional_malaise, unrefreshing_sleep_or_sleep_disturbance, cognitive_brain_fog_concentration, orthostatic_intolerance, mood_anhedonia_psych_features, pain_widespread_arthralgiaadvance: Phenotype tentative
- 3CONTEXTAge + sex + medication review (β-blocker, antihistamine, BZD, opioid, antidepressant, statin) + chronic disease (DM, CKD, HF, COPD, cancer) + infection history (HIV, HCV, TB, EBV, Lyme) + post-COVID / postviral + lifestyle (caffeine, alcohol, sleep hygiene, exercise) + rheumatologic family + sleep quality (STOP-BANG, Epworth) + weight / appetite / temperature intoleranceinputs: age, sex, medication_review_beta_blocker_antihistamine_bzd_opioid_antidepressant, chronic_disease_history_dm_ckd_hf_copd_cancer, infection_history_hiv_hcv_tb_ebv_lyme, recent_acute_illness_postviral_post_covid, lifestyle_caffeine_alcohol_exercise_sleep_hygiene, rheumatologic_family_autoimmune_history, sleep_quality_snoring_witnessed_apnea_stop_bang, weight_change_appetite_temp_intolerance, phq9_geriatric_depression_scaleadvance: Context comprehensive + medication audit complete
- 4RED_FLAGSRed flags requiring ED / urgent workup: new focal neuro deficit, severe chest pain, syncope, severe weight loss >10%, hemoptysis, painless lymphadenopathy >2 cm, severe SOB; severe depression with suicidal ideation; severe thyrotoxicosis; new DKA; severe anemia with hemodynamic instabilityinputs: red_flags_neuro_cardiac_severe_systemicadvance: Red flags ruled out OR ED routed
- 5INITIAL_WORKUPCBC + diff (anemia, leukocytosis, lymphocytosis); BMP + glucose (DM, CKD, electrolytes); LFT + albumin (hepatic, alcohol, nutrition); TSH + T4 (thyroid); HbA1c (DM); B12 + folate + iron studies (deficiencies); CRP + ESR (inflammation); HIV + HCV (universal screens); UA; PHQ-9 / GDS (depression); STOP-BANG + Epworth (sleep)inputs: cbc_with_diff, bmp_glucose_electrolytes, lft_albumin, tsh_t4_free, hba1c_fasting_glucose, b12_folate_iron_studies, crp_esr_inflammation, hiv_universal_screen, hcv_screen_universal, urinalysisactions: panel.cbc, panel.renal, panel.lft, panel.thyroid, panel.inflammation, panel.ironadvance: Tier 1 returned + cause stratification preliminary
- 6BRANCHING_WORKUPAnemia found → route symptom.anemia-workup.v1. Hypothyroid → levothyroxine; hyperthyroid → methimazole (severe → endo.thyroid-storm). DM → route endo.dm2.core.v1. CKD → route neph.ckd.core.v1. HF features → echocardiogram → route cardio.hfref.core.v1 if EF<40%. HIV/HCV → route ID engines. Sleep disorder → polysomnography. Depression → route psych.depression.core.v1. Rheumatologic features → ANA / RF / anti-CCP / ANCA / rheumatology referral. Adrenal insufficiency screen if orthostatic + hyperpigmentation + hyponatremia. TB / Lyme if endemic. Post-COVID → multidisciplinary clinic / route id.covid19.core.v1. ME/CFS IOM 2015 criteria evaluated as diagnosis of exclusion + symptom criteria.inputs: cortisol_acth_morning, ana_rf_anti_ccp_anca_if_rheum_features, tb_igra_if_endemic, lyme_serology_if_endemic_tick_exposure, epworth_sleepiness_scale, cxr_if_pulmonary_features, echocardiogram_if_cardiac_features, polysomnography_if_stop_bang_highadvance: Targeted workup complete or routed to specific engine
- 7DIFFERENTIALSleep disorders (~20-30% — OSA, narcolepsy, RLS, PLMD); Depression / psychiatric (~20% — most common in primary care); Anemia (~10-15%); Endocrine (~10% — hypothyroid most common); DM uncontrolled; CKD uremic; Cardiac low-output (HFrEF); Chronic infection (~5% — HIV, HCV, TB, EBV); Malignancy / paraneoplastic; ME/CFS (~1-2% — IOM 2015 criteria); Fibromyalgia overlap; Post-COVID / long COVID (significant post-2020); Medication-induced (~10%); Deconditioning / lifestyle; B12 / folate deficiency; Adrenal insufficiency; Rheumatologic; Undiagnosed (~20% — many self-resolve or evolve)advance: Differential ranked
- 8RISK_STRATIFICATIONSeverity by functional impact (housebound, bedbound, work-impaired); IOM 2015 ME/CFS criteria (all required for dx); fibromyalgia ACR 2016 (widespread pain index + symptom severity); depression by PHQ-9 (10-14 moderate, 15-19 moderately severe, ≥20 severe); sleep disorder severity (AHI grading); cardiac functional class (NYHA); CKD stage; cancer screening riskadvance: Risk-stratified disposition documented
- 9TREATMENTCause-directed: depression → SSRI / SNRI + psychotherapy (CBT); anemia → route + supplementation; hypothyroid → levothyroxine; hyperthyroid → methimazole / RAI / surgery; DM → glycemic control + lifestyle; CKD → dietary + dialysis planning; HF → GDMT (β-blocker, ACE-I/ARNI, MRA, SGLT2i); OSA → CPAP / BiPAP / oral appliance / weight loss / positional therapy; ME/CFS → pacing + symptom mgmt (NOT graded exercise therapy per IOM 2015 / CDC PMID 26561523 — verify); fibromyalgia → duloxetine / pregabalin / SNRI + aerobic exercise + CBT; long COVID → multidisciplinary + symptom mgmt + pacing; medication deprescribing; sleep hygiene + lifestyle counseling; adrenal insufficiency → hydrocortisone replacement; rheumatologic → DMARD / biologic per specialistinputs: medication_review_beta_blocker_antihistamine_bzd_opioid_antidepressantadvance: Treatment initiated or routed to specific engine
- 10DISPOSITIONHome (most): outpatient stepwise workup + lifestyle counseling + return precautions; subspecialty referral: GI / endocrine / psych / sleep medicine / cardiology / nephrology / pulmonary / rheumatology / ID / oncology; multidisciplinary clinic for ME/CFS / fibromyalgia / long COVID; ED if severe red flags (suicidal ideation, severe thyrotoxicosis, DKA, severe anemia with hemodynamic instability); inpatient rare (psych admission, severe medical decompensation)advance: Disposition assigned
- 11MONITORINGSymptom diary (energy, sleep, mood, pain, cognition); PHQ-9 trend if depression-treated (4-6 wk after SSRI); TSH 6 wk after thyroid therapy; HbA1c 3 mo after DM tx; CBC if anemia treated; polysomnography result + CPAP compliance / titration; ME/CFS pacing diary; fibromyalgia response to duloxetine / aerobic exercise; long COVID multidisciplinary follow-up; medication deprescribing reviewadvance: Monitoring plan in place
- 12FOLLOWUPLifestyle reinforcement (sleep hygiene, graded activity, nutritional counseling, caffeine reduction, alcohol moderation); psychiatry follow-up (CBT, SSRI/SNRI); chronic disease optimization; cancer screening intervals; sleep clinic for CPAP compliance; ME/CFS pacing (NOT GET); fibromyalgia multidisciplinary; long COVID rehab; rheumatology follow-up; geriatric long-term planningadvance: Long-term plan documented + follow-up scheduled