Table 3.
Frequency of episodes that reported matching and/or ambiguous/other d-lactic acidosis (d-la) symptoms as a function of age and sex
| ME/CFS ICC | d-La symptom overlap with ME/CFS | Episode frequencies | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Paediatric (≤17 years) | Adult (≥18 years) | Total | ||||||||||||||
| Male (15 episodes) | Female (6 episodes) | NI (1 episode) | Total (22 episodes) | Male (20 episodes) | Female (17 episodes) | Total (37 episodes) | (59 episodes) | |||||||||
| n | % | n | % | n | n | % | n | % | n | % | n | % | n | % | ||
| A. Postexertional neuroimmune exhaustion | Matching | 8 | 53.3 | 1 | 16.7 | – | 9 | 40.9 | 2 | 20.0 | 4 | 23.5 | 6 | 16.2 | 15 | 25.4 |
| Ambiguous/other | – | – | – | – | – | – | – | – | – | – | – | – | – | – | – | |
| B. Neurological impairments | Matching | 12 | 80.0 | 6 | 100 | 1 | 19 | 86.4 | 18 | 90.0 | 15 | 88.3 | 33 | 89.2 | 52 | 88.1 |
| Ambiguous/other | 11 | 73.3 | 2 | 33.3 | 1 | 14 | 63.6 | 17 | 85.0 | 14 | 82.4 | 31 | 83.8 | 45 | 76.3 | |
| Ambiguous/other B1–B4 | 3 | 20.0 | 1 | 16.7 | 1 | 5 | 22.7 | 11 | 55.0 | 6 | 35.3 | 17 | 45.9 | 22 | 37.3 | |
| Speech/language | 7 | 46.7 | 2 | 33.3 | 1 | 10 | 45.5 | 11 | 55.0 | 9 | 52.9 | 20 | 54.1 | 30 | 50.8 | |
| Consciousness | 5 | 33.3 | – | – | – | 5 | 22.7 | 5 | 25.0 | 3 | 17.6 | 8 | 21.6 | 13 | 22.0 | |
| C. Immune, gastrointestinal, genitourinary impairments | Matching | 3 | 20.0 | – | – | – | 3 | 13.6 | 6 | 30.0 | 4 | 23.5 | 9 | 24.3 | 12 | 20.3 |
| Ambiguous/other | – | – | – | – | – | – | – | – | – | – | – | – | – | – | – | |
| D. Energy production/transportation impairments | Matching | 8 | 53.3 | 3 | 50.0 | – | 11 | 50.0 | 7 | 35.0 | 2 | 11.8 | 9 | 24.3 | 20 | 33.9 |
| Ambiguous/other | – | – | – | – | – | – | – | 2 | 10.0 | – | – | 2 | 5.4 | 2 | 3.4 | |
| Mood/behavior | Matching | 2 | 13.3 | 1 | 16.7 | – | 3 | 13.6 | 2 | 10.0 | 3 | 17.6 | 5 | 13.5 | 8 | 13.6 |
| Ambiguous/other | 6 | 40.0 | – | – | – | 6 | 27.3 | 4 | 20.0 | 3 | 17.6 | 7 | 18.9 | 13 | 22.0 | |
| Uncategorized d-la symptoms | ||||||||||||||||
| Metabolic acidosis | 15 | 100 | 6 | 100 | 1 | 22 | 100 | 20 | 100 | 16 | 94.1 | 36 | 97.3 | 58 | 98.3 | |
| Other abnormalities | 4 | 26.7 | – | – | – | 4 | 18.2 | 6 | 30.0 | 2 | 11.8 | 7 | 18.9 | 11 | 18.6 | |
Percentages were calculated from fractions of the number of episodes that reported relevant symptoms (n) against the number of possible episodes (noted in column subheadings) within each sex and age category. ME/CFS broad category B Neurological impairments are highlighted as the primary focus of this review. The ambiguous/other symptoms are further delineated into three subcategories (ICC criteria B1–B4, speech/language symptoms, and level of consciousness; see Table 2 for explanations). In each subcategory the same episode code number can be shown several times to represent multiple symptoms during each d-la episode. See Additional file 2: Table S2 for an expansion of these results showing episode code numbers that were included for each symptom category
Ambiguous/other symptoms that were not clearly identified as consistent with ME/CFS presentation (see Table 2 for detailed symptom delineation), B1–B4 neurocognitive impairments, pain, sleep disturbances, neurosensory and perceptual, motor disturbances, d-la d-lactic acidosis, ICC International Consensus Criteria, Matching mapped overlap between ME/CFS and d-la symptoms, ME/CFS myalgic encephalomyelitis/chronic fatigue syndrome, NI sex not identified