Mixed autoimmune hemolytic anemia explained

Mixed autoimmune hemolytic anemia
Specialty:	Hematology

Mixed autoimmune hemolytic anemia (MAIHA) is a type of autoimmune hemolytic anemia which combines the features of cold sensitive antibody-induced diseases and warm autoimmune hemolytic anemia. The work-up for diagnosis is complex and the condition can be over-diagnosed.^{[1] [2]}

People diagnosed with warm autoimmune hemolytic anemia (WAIHA) caused by immunoglobulin G (IgG)^[3] may also have a high number of immunoglobulin M (IgM) antibodies. These antibodies are active at room temperature, but are believed to be harmless since they are not the main antibodies responsible for WAIHA.

However, studies revealed the existence of a few cases of WAIHA that may also carry cold agglutinin antibodies that are active at the environment where the temperatures is generally equal to or warmer than 30 °C (86 °F). Such coexistence suggests a diagnosis of the mixed (warm- and cold-antibody) autoimmune hemolytic anemia abbreviated as MAIHA.^[4]

Mixed warm and cold AIHA runs a chronic course with severe intermittent exacerbations, such as serious anemia, and is treated by blood transfusion. Successful therapeutic options for the treatment of hemolysis associated with mixed AIHA are limited but increasing.^{[5] [6]}

In the past, there were two obvious sources of error regarding the diagnosis of AIHA. First, patients with w-AIHA can produce low-titer, low-thermal amplitude CA of no clinical significance. Second, up to 20% of patients with CAD have IgG on the RBC surface in addition to C3d.^{[7] [1] [6]}

See also

• Thermal amplitude (medical)

Notes and References

1. Mayer . Beate . Yürek . Salih . Kiesewetter . Holger . Salama . Abdulgabar . Mixed-type autoimmune hemolytic anemia: differential diagnosis and a critical review of reported cases . Transfusion . Wiley . 48 . 10 . 2008 . 0041-1132 . 18564390 . 10.1111/j.1537-2995.2008.01805.x . 2229–2234. 46182439 .
2. Berentsen . Sigbjørn . Sundic . Tatjana . Red Blood Cell Destruction in Autoimmune Hemolytic Anemia: Role of Complement and Potential New Targets for Therapy . BioMed Research International . Hindawi Limited . 2015 . 2015-01-29 . 363278 . 2314-6133 . 25705656 . 4326213 . 10.1155/2015/363278 . free .
3. Web site: Orphanet: Autoimmune hemolytic anemia, warm type . Orphanet . 2019-02-14 . 2019-02-15.
4. Das . SudiptaSekhar . Chakrabarty . Ritam . Zaman . RU . Immunohematological and clinical characterizations of mixed autoimmune hemolytic anemia . Asian Journal of Transfusion Science . Medknow . 12 . 2 . 2018 . 99–104 . 0973-6247 . 10.4103/ajts.ajts_105_17 . 30692792 . 6327768 . free .
5. Gupta . Shilpi . Szerszen . Anita . Nakhl . Fadi . Varma . Seema . Gottesman . Aaron . Forte . Frank . Dhar . Meekoo . Severe refractory autoimmune hemolytic anemia with both warm and cold autoantibodies that responded completely to a single cycle of rituximab: a case report . Journal of Medical Case Reports . Springer Nature . 5 . 1 . 2011-04-19 . 156 . 1752-1947 . 21504611 . 3096571 . 10.1186/1752-1947-5-156 . free .
6. Berentsen . Sigbjørn . Sundic . Tatjana . Red Blood Cell Destruction in Autoimmune Hemolytic Anemia: Role of Complement and Potential New Targets for Therapy . BioMed Research International . Hindawi Limited . 2015 . 2015-01-29 . 2314-6133 . 25705656 . 4326213 . 10.1155/2015/363278 . 363278-1–363278-11. free .
7. Berentsen . S . Ulvestad . E . Langholm . R . Beiske . K . Hjorth-Hansen . H . Ghanima . W . Sørbø . JH . Tjønnfjord . GE . Primary chronic cold agglutinin disease: a population based clinical study of 86 patients. . Haematologica . 91 . 4 . 2006 . 0390-6078 . 16585012 . 460–6.