14 April 2026
: Case report 
Hemoglobin San Diego: A Case Report and Review of the Literature
Challenging differential diagnosis, Rare disease
Matthew L. Repp ABEF 1*, Brandon McMahon ABEF 1,2DOI: 10.12659/AJCR.951364
Am J Case Rep 2026; 27:e951364
Table 2 Summary of hemoglobin San Diego cases in the literature including patient demographics, clinical presentation, laboratory findings, family history, and any interventions performed.
| Author, year [ref] | Sex, age (years) | Clinical presentation | Ethnicity/ancestry | Laboratory values (Hb g/dL; Hct%) | Family history | Interventions |
|---|---|---|---|---|---|---|
| Nute et al, 1974 []6 | Female, 37 | Headaches and dizziness | Filipino | Hb: 18Hct: 52 | Six family members, including sister and children | None reported |
| Chanarin et al, 1975 []22 | Male, 63 | Initially asymptomatic; later splenic hematoma, postoperative bleeding, DVT/PE, plethoric facies | Not reported | Hb: 19.4Hct: Not reported | Brother had Hb San Diego; father presumed affected (premature death) | None reported |
| Harkness et al, 1981 []23 | Female, 79 | Ecchymosis, purpura while on warfarin and phenylbutazone, subcutaneous hemorrhages, mild headaches | English, Scottish | Hb: 20.4Hct: 64 | Father and paternal grandfather underwent blood removal by leeches | None reported |
| Rochette et al, 1984 []24 | Male, 16 | None reported | Tunisian | Hb: 18.3Hct: 54.2 | None reported | None reported |
| Loukopoulos et al, 1986 []25 | Male, 29 | Facial plethora, splenomegaly | Greek | Hb: 19.1Hct: 70 | None reported | Phlebotomy during episodes of headache or dizziness |
| Coleman et al, 1993 []26 | Female, 35 | None reported | Iranian | Hb: 18.0Hct: Not reported | Brother and sister with unspecified erythrocytosis | None reported |
| Williamson et al, 1995 []26 | Male, 30 | Colicky abdominal pain | West Indian | Hb: 18.8Hct: 58 | No Hb San Diego in parents or sister; mother and sister had Hb S mutation | Phlebotomy |
| Gerli et al, 2002 []27 | Female, 57 | Transient respiratory distress, arrhythmias, mild facial plethora | Italian | Hb: 18.9Hct: 70 | None reported | None reported |
| Keskin et al, 2017 []14 | Female, 15 | Occasional headaches, fatigue, dizziness, nausea, chest pain | Turkish | Hb: 16.9Hct: 50.6 | Father and paternal grandmother had erythrocytosis requiring multiple phlebotomies; 2 aunts, 1 uncle, and 2 cousins had erythrocytosis | None reported |
| Boster et al, 2019 []28 | Male, 18 | Asymptomatic | White (Texas, USA) | Hb: 17.8Hct: 52.1 | Mother and maternal grandmother had erythrocytosis requiring intermittent phlebotomy | None reported |
| Xiong and Chen, 2019 []15 | Male, 43 | Intermittent headaches and dizziness | Chinese | Not reported | Erythrocytosis in 6 family members across 3 generations | Occasional phlebotomies |
| Oo, 2020 []29 | Male, 41 | Palmar plethora | Hispanic | Hb: 18.4Hct: 56.3 | Brother with erythrocytosis | None reported |
| This case | Male, 29 | Splenomegaly (otherwise asymptomatic) | White (Colorado, USA) | Hb: 18.7Hct: 53.9 | None reported | None reported |
| DVT – deep vein thrombosis; Hb – hemoglobin; Hct – hematocrit; Hb S – hemoglobin S; PE – pulmonary embolism. | ||||||