Buffalo Humps Research Articles

LMNA Mutations Induce a Non-Inflammatory Fibrosis and a Brown Fat-Like Dystrophy of Enlarged Cervical Adipose Tissue

Some LMNA mutations responsible for insulin-resistant lipodystrophic syndromes are associated with peripheral subcutaneous lipoatrophy and faciocervical fat accumulation. Their pathophysiologic characteristics are unknown. We compared histologic, immunohistologic, ultrastructural, and protein expression features of enlarged cervical subcutaneous adipose tissue (scAT) obtained during plastic surgery from four patients with LMNA p.R482W, p.R439C, or p.H506D mutations versus cervical fat from eight control subjects, buffalo humps from five patients with HIV infection treated or not with protease inhibitors, and dorsocervical lipomas from two patients with mitochondrial DNA mutations. LMNA-mutated cervical scAT and HIV-related buffalo humps were dystrophic, with an increased percentage of small adipocytes, increased fibrosis without inflammatory features, and decreased number of blood vessels, as compared with control samples. Samples from patients with LMNA mutations or protease inhibitor-based therapy demonstrated accumulation of prelamin A, altered expression of adipogenic proteins and brown fat-like features, with an increased number of mitochondria and overexpression of uncoupling protein 1 (UCP1). These features were absent in samples from control subjects and from patients with HIV not treated with protease inhibitors. Mitochondrial DNA-mutated cervical lipomas demonstrated inflammatory fibrosis with distinct mitochondrial abnormalities but neither UCP1 expression nor prelamin A accumulation. In conclusion, Enlarged cervical scAT from patients with lipodystrophy demonstrated small adipocytes, fibrosis, and decreased vessel numbers. However, only cervical fat from patients with LMNA mutations or who had received protease inhibitor therapy accumulated prelamin A and exhibited similar remodeling toward a brown-like phenotype with UCP1 overexpression and mitochondrial alterations.

CT and MRI findings of Madelung syndrome

Objective To determine the CT and MR findings of Madelung syndrome. MethodsFive cases of Madelung syndrome were collected in our hospital from February 2006 to June 2009, including 3 cases of typeⅠMadelung syndrome and 2 cases of typeⅡ Madelung syndrome. The 5 cases were all examined by CT, meanwhile 1 case by CT enhancement scanning and 2 cases by MR. The clinical characteristics and imaging manifestations were analyzed. Results CT and MR images in 3 patients of typeⅠMadelung syndrome displayed fat accumulation within the subcutaneous tissue of the upper trunk and deep layer tissue of neck. The diffuse masses were located around the neck, upper chest and shoulders, which were called horse collarand buffalo humps. The other 2 cases of type Ⅱ Madelung syndrome displayed fat thickening within the subcutaneous tissue of the proximal extremities, anterior chest wall, showing special appearance of vigorous sailor. All the 5 patients showed fat deposit within the subcutaneous tissue of the anterior rectus abdominis, inguina and fat accumulation within the scrotum. CT showed proliferated fat at the subcutaneous tissue of the involved regions. The CT value of proliferated fat were between -30 and -70 HU. The proliferated fat tissue all could be displayed on MR T1WI,T2WI and T2WI fat suppression sequence, with typical hypointensity on T1WI and hyperintensity on T2WI, hypointensity on fat-suppression sequence and fibrous septation presenting among fat tissue. Conclusion Combination with the history of long-term alcohol abuse, the Madelung syndrome could be diagnosed by CT and MR, which had great value in the surgical planning for identifying the extent of disease. Key words: Lipomatosis, multiple symmetrical; Tomography,X-ray computed; Magnetic resonance imaging

Prevalence of and Risk Factors for Pubic Lipoma Development in HIV-Infected Persons

The natural history of HIV-associated body habitus changes is unclear. In this report, we describe a novel manifestation of HIV-associated lipoaccumulation. We noted the presence of suprapubic fat pads (pubic lipomas [PLs]) in several patients with preexisting HIV-associated body habitus abnormalities. Subsequently, we evaluated the prevalence of and associated risk factors for development of PLs by undertaking an observational cross-sectional study among patients with known lipodystrophy who attended a metabolic clinic in northern Italy. Inclusion criteria were a physician-confirmed diagnosis of lipodystrophy according to the Multicenter AIDS Cohort Study definition and, for those affected with PL, a readily noticeable PL on physical examination. We evaluated 582 patients with lipodystrophy: 214 female (36.7%) and 368 male (63.3%). The overall PL prevalence was 9.4% (95% confidence interval [CI]: 7.2% to 12.1%; P < 0.0001). PLs were more common among obese than nonobese individuals (34.5%, 95% CI: 17.9% to 5l.3% vs. 8%, 95% CI: 5.9% to 10.6%, respectively; P < 0.0001) and those with preexisting dorsocervical fat pads, commonly called "buffalo humps" (BHs) (18.5%, 95% CI: 12.7% to 25.4% vs. 6.1%, 95% CI: 4.03% to 8.83%, respectively, P < 0.0001; relative risk = 3.02, 95% CI: 1.84% to 4.96%, P < 0.0001). The PL prevalence in the nonobese HIV-infected population (body mass index [BMI] <30, n = 550) was 8.0% (95% CI: 5.9% to 10.6%; P < 0.0001). Logistic regression analyses identified the following factors as associated with a greater likelihood for PL: BMI >30 (beta = 0.18, SE = 0.04; P < 0.001), female gender (beta = 1.06, SE = 0.31; P < 0.001), and shorter duration of HIV infection (beta = -0.005, SE = 0.003; P = 0.04). We used a chain graph model to evaluate risk factors for BH and PL simultaneously. A nonnull interaction between these entities was evident, and this association seemed to be independent of factors positively associated with both (BMI and gender). PL is a newly recognized manifestation of HIV-associated lipoaccumulation that is more likely to occur among those with coexisting dorsocervical fat pads, suggesting the possibility of a common pathogenesis between the 2 entities. Likewise, PLs are more common among women, obese individuals, and those with a shorter duration of HIV infection. We suggest that PL should be considered part of the HIV-associated lipodystrophy syndrome.

Potential of Recombinant Human Growth Hormone in HIV-Associated Adipose Redistribution Syndrome

HIV infection recently has been complicated by the emergence of a rare metabolic dysmorphic disorder characterised by fat atrophy, redistribution and accumulation in the setting of hyperlipidaemia and, on occasion, hyperglycaemia. The disorder, sometimes referred to as HIV-associated Adipose Redistribution Syndrome (HARS), has a prevalence rate of about 50 to 60% and seems temporally related to the advent of highly active antiretroviral therapy, especially the usage of protease inhibitors. Various studies also implicate the nucleoside analogues stavudine, didanosine and lamivudine in the pathogenesis of HARS, especially fat atrophy. It is uncertain whether the changes described in HARS represent a single syndrome or a group of related syndromes. Reports have noted differences between morphologic and metabolic changes. More recently, it has been suggested that fat atrophy and fat accumulation may also be separate entities. There are several potential pathogenic theories for HARS that implicate both protease inhibitors and nucleoside analogues as causative agents. However, long term HIV infection rather than any specific agent or class of agent may be the source. Recombinant human growth hormone (rhGH) is a mammalian cell-derived product, which has been useful in a variety of human disorders ranging from pituitary dwarfism to septic shock. It has anabolic, immunological and metabolic properties that restore normal functioning to many aberrant disease pathways. The lipolytic properties of rhGH have been especially beneficial in the diminution of localised fat accumulation in the dorsocervical area (buffalo humps) and truncal region. This has been observed in various reports where rhGH has been administered at doses of 5 to 6 mg/day in patients with HARS for periods ranging from 3 months to >2 years. Relapses after discontinuation of rhGH occurred in most patients. Adverse effects included carpal tunnel syndrome, facial swelling, arthralgias and myalgias and worsening or onset of hyperglycaemia. The small uncontrolled studies conducted to date suggest that the most notable effect of rhGH treatment is the reduction of truncal adiposity and buffalo humps and that the agent has little effect on restoring the adiposity of the appendicular muscles, buttocks or face. Although most patients with HARS have associated hyperlipidaemia, rhGH has no notable effect on serum cholesterol and triglyceride levels. However, blood glucose levels can increase and pre-existent diabetes mellitus may worsen. A short term confirmatory placebo-controlled trial in patients with HARS is urgently needed, as are comparative trials using other anabolic agents such as oxandrolone and testosterone.

Unusual distributions of body fat in AIDS patients: a review of adverse events reported to the Food and Drug Administration.

This report summarizes postmarketing adverse events reported to the Food and Drug Administration (FDA) that describe unusual or abnormal fat distribution in association with anti-retroviral therapies. Reports associated will protease inhibitors were compared to those associated with non-protease inhibitor antiretroviral therapies. The Spontaneous Reporting System (SRS) and Adverse Event Reporting System (AERS) of the FDA MEDWATCH post-marketing surveillance system served as the database. Four protease inhibitors (saquinavir, indinavir, nelfinavir, and ritonavir) and seven nonprotease inhibitors (zidovudine, didanosine, zalcitabine, stavudine, lamivudine, nevirapine, and delavirdine) were searched for reports relating to: weight increase, unusual fat deposition, Cushing's syndrome, or Cushingoid appearance. Each drug was searched for its "life" from time of initial approval through a uniform database cutoff of March 18, 1998. A total of 62 cases of abnormal fat accumulation were reported in association with one or several of the four approved protease inhibitors compared to three cases reported in association with the seven non-protease inhibitor based therapies. Case descriptions varied, and included abdominal fat accumulation, breast enlargement, thick necks, buffalo humps, multiple lipomatous growths, Cushingoid features, centralized fat redistribution, and mesenteric, omental, and retroperitoneal fat accumulation. Some subjects switched or stopped their antiretroviral therapy, others underwent surgery to remove the fat, and many considered their symptoms disabling. The pathophysiologic mechanism for these events remains unclear and a causal link to a specific drug or drug class is uncertain. Patients and clinicians reporting to the MEDWATCH system, however, have clearly associated the development of abnormal body fat with protease inhibitors as opposed to other antiretroviral therapies.

“Buffalo Humps” Associated with Protease Inhibitors

“Buffalo Humps” Associated with Protease Inhibitors

Plastic Buffalo Humps: Theory as Sludge in the Journal of Higher Education: Comment

Plastic Buffalo Humps: Theory as Sludge in the Journal of Higher Education: Comment

Plastic Buffalo Humps: Theory as Sludge in theJournal of Higher Education

(1991). Plastic Buffalo Humps: Theory as Sludge in the Journal of Higher Education. The Journal of Higher Education: Vol. 62, No. 6, pp. 682-694.

Medicine's Metaphors: Messages &amp;amp; Menaces

In<i>Medical Metaphors</i>Samuel Vaisrub extends the concept of metaphor to encompass all borrowing or extrapolation of concepts and theories from one discipline to another. For this kind of exercise, medicine is clearly a fruitful field, for it is endowed with a vocabulary that is colorful and evocative, though likely to produce a permanent aversion to such articles as nutmeg and sago pudding, not to mention rice-water, pea soup, and currant jelly. The book, opening with the metaphorical but now extinct housemaid and her inflamed bursa, is divided, like Gaul,<i>in partes tres</i>. "Inflow" brings together all that medicine owes to war, the criminal world, mythology, fiction, dreams, religion, and the sciences. Among animals the lion is underrepresented, with only leontiasis ossea and the leonine facies of leprosy; but the other beasts get a lion's share with tigroid fundi, lupus vulgaris, leopard spots, buffalo humps, staghorn calculi, elephantiasis, hare lips,