Table 2.
Clinical Characteristics of Patients With Non-Keratitis Acanthamoeba Infections, United States, 1956–2020
| Characteristic | Total, No. (%) | Confirmed, No. (%) | Suspected. No. (%) |
|---|---|---|---|
| Organ system involvementa | |||
| GAE | 122 (71) | 105 (61) | 17 (10) |
| Cutaneous | 79 (46) | 71 (41) | 8 (5) |
| Rhinosinusitis | 51 (29) | 30 (17) | 21 (12) |
| Pulmonary | 23 (13) | 17 (10) | 6 (3) |
| Osteomyelitisb | 10 (6) | 8 (5) | 2 (1) |
| Non-keratitis eye diseasec | 5 (3) | 2 (1) | 3 (2) |
| Liver | 4 (2) | 2 (1) | 2 (1) |
| Adrenals | 3 (2) | 3 (2) | 0 |
| Kidney | 3 (2) | 2 (1) | 1 (1) |
| Lymph nodes | 2 (1) | 2 (1) | 0 |
| Breast | 1 (1) | 1 (1) | 0 |
| Heart | 1 (1) | 1 (1) | 0 |
| Spleen | 1 (1) | 1 (1) | 0 |
| Testicle | 1 (1) | 1 (1) | 0 |
| Thyroid | 1 (1) | 1 (1) | 0 |
| Urethra | 1 (1) | 1 (1) | 0 |
| Total No. of organs infected, confirmed or suspected | |||
| 1 | 92 (53) | … | … |
| 2 | 51 (29) | … | … |
| 3 | 18 (10) | … | … |
| 4 | 6 (3) | … | … |
| 5 | 4 (2) | … | … |
| 8 | 2 (1) | … | … |
| Disease presentation | |||
| CNS involvement | |||
| GAE only | 67 (39) | … | … |
| GAE and cutaneous disease | 17 (10) | … | … |
| GAE and rhinosinusitis | 7 (4) | … | … |
| Other GAE disseminated | 31 (18) | … | … |
| No CNS involvement | |||
| Cutaneous disease only | 16 (9) | … | … |
| Rhinosinusitis only | 7 (4) | … | … |
| Pulmonary only | 1 (1) | … | … |
| Osteomyelitis only | 1 (1) | … | … |
| Cutaneous disease and rhinosinusitis | 17 (10) | … | … |
| Other disseminated (does not include GAE) | 9 (5) | … | … |
| Outcome | |||
| Survived | 26 (15) | … | … |
| Died | 122 (71) | … | … |
| Unknown | 25 (14) | … | … |
| Immunocompromising condition | |||
| HIV infection | 67 (39) | … | … |
| Cancer | 48 (28) | … | … |
| Hematologic malignancyd | 39 (23) | … | … |
| Solid organ transplant | 31 (18) | … | … |
| HSCTe | 18 (10) | … | … |
| Diabetes mellitus | 17 (10) | … | … |
| Autoimmune disease | 14 (8) | … | … |
| Illicit drug use | 11 (6) | … | … |
| Alcoholism | 9 (5) | … | … |
| Malnourished | 2 (1) | … | … |
| Other immunocompromising conditionf | 5 (3) | … | … |
| None/unknown | 21 (12) | … | … |
| Exposures | |||
| Soil exposureg | 19 (11) | … | … |
| Water exposureh | 18 (10) | … | … |
| Nasal irrigation | 8 (5) | … | … |
| Occupational exposurei | 4 (2) | … | … |
Data are presented as No. (%) unless otherwise indicated.
Abbreviations: CNS, central nervous system; GAE, granulomatous amebic encephalitis; HIV, human immunodeficiency virus; HSCT, hematopoietic stem cell transplant.
Percentages may add up to >100%, as patients could be included in >1 category.
Many cases of rhinosinusitis described bony erosion into the hard palate on imaging; those cases are not included in the osteomyelitis category.
Eye disease includes 3 cases of endophthalmitis, 1 case of granulomatous uveitis, and 1 case of iritis.
Patients with a hematologic malignancy were included in “Cancer” category as well; types of hematologic malignancy included chronic lymphocytic leukemia (13), non-Hodgkin lymphoma (8), acute myeloid leukemia (7), acute lymphocytic leukemia (5), chronic myeloid leukemia (2), Hodgkin lymphoma (2), T-cell prolymphocytic leukemia (1), unspecified lymphoma (1), and unspecified hematologic malignancy (1). One patient had 2 hematologic malignancies.
Includes bone marrow transplant and stem cell transplant.
Includes pregnancy, asplenia, primary immunodeficiency, and posttransplant lymphoproliferative disease.
Soil exposures included gardening (14), farming (4), and other (6), including yard work, mulch exposure, and outdoor recreation. Some patients reported multiple exposures.
Water exposures included lakes (4), oceans (2), well water (2), swimming pools (6), water park (1), and other (8), including creeks, home medical machines, home fish tanks, and sewage exposure. Some patients reported multiple exposures. This category does not include patients who reported nasal irrigation.
Occupational exposures included architect, landscaper, gardener, and working with animals.