Characteristics of the groups
Overall, of the 76 patients referred for suspicion of lipodystrophy syndromes, 56 were excluded, whom 52 for other types of lipodystrophy syndromes and four because of insufficient data, death or persistent diagnostic doubt. Twenty lipomatosis cases were finally included:
- 9 patients with Dercum's disease (3 men and 6 women)
- and 11 patients with Roch-Leri lipomatosis (7 men and 4 women).
In addition, 18 healthy normal weight controls (10 men and 8 women) were included, resulting in a total of 38 patients (20 men and 18 females) (Figure 1-I).
Clinical characteristics of the Dercum’s disease group
As shown in Table 1, the sex ratio was 2:1 for women and men, with a median age of 30 years and a BMI of 32.5 kg/m2. The lipomas were mainly distributed on the thighs (67%), back (54%) and forearms (56%). Most patients (89%) had more than 10 lipomas (Figure 1-II). The ultrasonographic characterization showed that 88% of lipomas were encapsulated, 11% were fibrotic, and 11% were ecchymotic. Pain, which was an inclusion criteria for the Dercum’s group, was present in 100% of cases, with 88% having paroxysmal pain and 12% with chronic pain. More than half of the patients (56%) had undergone at least one surgery, and the pathological analysis confirmed the diagnosis of lipoma in all cases. Res-pectively, 11%, 22% and 33% were treated for dyslipidemia, hypertension and diabetes before the diagnosis. For the pain, 33% of patients used level I and 56% level II analgesics; 36% received mood modulators (benzodiazepines and antidepressants) and 22% anti-epileptics. The proportion of immune function disorders in the personal history of the Dercum’s patients was 22%. Eleven percent of the patients had a family history of first- degree lipomatosis.
Clinical characteristics of the Roch-Leri group
As displayed in Table 1, the sex ratio showed a male predominance, and patients had a median age of 31 years and a BMI of 30.8 kg/m2. The painless lipomas were mainly located on the forearms (82%), thighs (73%) and abdomen (55%) (Figure 1-II). More than 80% of patients (82%) had more than 10 lipomas, which were always encapsulated, and 11% were fibrotic. Around half of the patients (54.5%) had undergone surgery for at least one lipoma, and the pathological analysis confirmed the diagnosis of lipoma in all cases. Respectively, 45%, 65% and 0% of patients were treated for dyslipidemia, hypertension and diabetes before the diagnosis. One case of diabetes was diagnosed with the OGTT (9% of the LMS group). None of the patients received long-term analgesics or mood stabilizing medications. The proportion of immune function disorders in the personal history concerned almost half of patients (45%). Around one-third of patients (27%) had a family history of first-degree lipomatosis.
Comparison of the Dercum’s disease and the Roch-Leri groups
Clinical phenotype
The sex ratio differed between the Dercum’s disease and LMS groups (p <0.05), with a predominance of men (63%) in the LMS group and of women (66%) in the Dercum’s group. There was no difference between the lipomatosis groups with regard to age at the time of the first assessment, around 31 years for the two groups. The location of lipomas did not differ significantly between the two groups except for a higher number of lipomas on forearms/arms in the LMS vs. the Dercum’s group (82% vs. 56%; p< 0.05). The frequency of patients with a number of lipomas above 10 (around 80-90%) and the percentage of patients who had had at least one lipoma surgery did not differ between the two groups despite the fact that lipomas were painful and required analgesics in Dercum’s disease (Table 1).
Metabolic phenotype
There were no differences in the lipid, liver enzyme, fasting glucose, insulin, C-peptide, HOMA-IR and leptin levels between the two groups (Table 2). Body composition parameters did not differ between the groups. The prevalence of treated hypertension, diabetes or dyslipidemia was similar (Table 1).
Immunohematological phenotype
The proportion of immune system disorders, such as vitiligo and dysthyroidism, in the Roch-Leri group (45%) tended to be higher than that observed in the Dercum’s group (22%), but the difference was not significant. Similarly, the blood cell count (hemoglobin, platelets, leukocytes) and the differential was similar between the Dercum’s and LMS groups except for the number of basophils, which was significantly higher (2.7 fold) in the Dercum’s than in the LMS group (p<0.001). Also, the lymphocyte subpopulation count showed that the LMS group had a significantly lower total CD 3+ T lymphocytes levels and CD4+ /CD8 + T lymphocytes subpopulations levels compared with the Dercum’s group (p <0.05) (Table 3 and Figure 3).
Comparison of the Dercum’s group with the healthy control group
Metabolic characteristics
Weight (p<0.05), BMI (p<0.01), systolic and diastolic blood pressure (p<0.05) and percentage of fat mass and intra-/total abdominal fat ratio (p<0.01) were significantly higher in the Dercum’s group than the control group (Table 2 and Figure 2). Likewise, the levels of gamma-GT, fasting blood glucose, insulin, C-peptide, HOMA-IR, LDL-cholesterol and leptin were significantly higher in the Dercum’s group than the control group (Table 2 and Figure 2). Age, triglycerides, HDL-cholesterol levels as well as liver enzymes did not differ between the Dercum’s and the healthy control groups.
Immunohematological characteristics
The levels of platelets and circulating leukocytes were significantly higher in the Dercum’s group than in the control group (Table 3). The leukocyte differential, and the levels of lymphocytes, monocytes, nuclear neutrophils, circulating eosinophils at diagnosis did not differ between the Dercum’s and the control groups. Only the levels of circulating basophils were significantly higher (52 fold) in the Dercum’s group compared with the control group (p<0.05). The lymphocyte subpopulation count did not differ between the Dercum’s and healthy control groups except for circulating natural killer (NK) cells, which were significantly lower in the Dercum’s disease group (p<0.05) compared with controls (Table 3 and Figure 3).
Comparison of the Roch-Leri -group with the healthy control group
Metabolic characteristics
Weight (p <0.05), BMI (p <0.01), systolic and diastolic blood pressure (p <0.05) and percentage of fat mass and intra-/total abdominal fat ratio (p<0.01) were significantly higher in the Roch-Leri group compared with the control group (Table 2 and Figure 2). Likewise, the levels of gamma-GT, fasting insulin, C-peptide, HOMA-IR and leptin were significantly higher in the Roch-Leri-group compared with the control group (Table 2 and Figure 2). Age, and levels of fasting blood glucose, lipids and liver enzymes did not differ between the Roch-Leri group and the healthy control group.
Immunohematological characteristics
The blood cell count and the leukocyte differential at diagnosis did not differ between the Roch-Leri group and the control group. The lymphocyte subpopulation count showed CD3+, CD4+, and CD8+ lymphocyte levels significantly lower (around 1.9 fold) in the Roch-Leri group compared with the control group (p<0.05) (Table 3 and Figure 3).