Platelet-rich plasma in the conservative treatment of painful tendinopathy: a systematic review and meta-analysis of controlled studies

BACKGROUND

Platelet-rich plasma (PRP) seeks to meet the multifaceted demand of degenerated tendons providing several molecules capable of boosting healing.

AREAS TIMELY FOR DEVELOPING RESEARCH

PRP is used for managing tendinopathy, but its efficacy is controversial.

SOURCES OF DATA

Electronic databases were searched for clinical studies assessing PRP efficacy. Methodological quality was evaluated using the methods described in the Cochrane Handbook for systematic reviews.

AREAS OF AGREEMENT

Thirteen prospective controlled studies, comprising 886 patients and diverse tendons were included; 53.8% of studies used identical PRP protocol.

AREAS OF CONTROVERSY

Sources of heterogeneity included different comparators, outcome scores, follow-up periods and diverse injection protocols, but not PRP formulation per se.

GROWING POINTS

Pooling pain outcomes over time and across different tendons showed that L-PRP injections ameliorated pain in the intermediate-long term compared with control interventions, weighted mean difference (95% CI): 3 months, -0.61 (-0.97, -0.25); 1 year, -1.56 (-2.27, -0.83). However, these findings cannot be applied to the management of individual patients given low power and precision.

RESEARCH

Further studies circumventing heterogeneity are needed to reach firm conclusions. Available evidence can help to overcome hurdles to future clinical research and bring forward PRP therapies.

Use of autologous platelet-rich clots for the prevention of local injury bleeding in patients with severe inherited mucocutaneous bleeding disorders

Stopping or preventing local bleeding in patients with inherited bleeding disorders linked to abnormal platelet function is traditionally treated by transfusion of blood cell products or recombinant factor VIIa. We now report the use in such patients of autologous platelet-rich clots as an aid to preventing bleeding and to facilitating tissue regeneration at superficial sites. Two patients with von Willebrand's disease (VWD) type 2B and one patient with type I Glanzmann thrombasthenia were treated after tooth extraction and dental surgery. A fourth patient with platelet-type VWD underwent a skin biopsy. Whereas all four patients had a lifelong history of bleeding complications, the application of an autologous platelet-rich clot immediately after surgery combined with tranexamic acid intake to slow fibrinolysis prevented blood loss and resulted in rapid and normal healing. This new procedure is simple, safe and inexpensive; it provides extra security for patients with a bleeding risk undergoing dentistry or superficial surgery.

Intra-articular injection of an autologous preparation rich in growth factors for the treatment of knee OA: a retrospective cohort study

OBJECTIVE

To obtain preliminary information about the effectiveness of intra-articular injections of an autologous preparation rich in growth factors (PRGF) for knee OA treatment to be explored further in future studies.

METHODS

We have characterized PRGF treatment by platelet count and concentration of relevant growth factors (TGF-Beta1, PDGF-AB, VEGF-A; HGF and IGF-I) involved in healing mechanisms. We have performed an observational retrospective cohort study using hyaluronan injections as a control. Each group included 30 patients with OA of the knee, matched according to age, sex, body mass index and radiographic severity. Both treatments were based on three weekly injections. Clinical outcome was examined using the WOMAC questionnaires prior to treatment and at 5 weeks after treatment.

RESULTS

The observed success rates by week 5 for the pain subscale reached 33.4% for the PRGF group and 10% for the hyaluronan group. The difference was attributed exclusively to the treatment modality, p = 0.004. The percent reductions in the physical function subscale and overall WOMAC at 5 weeks were also associated solely with treatment modality in favour of PRGF, p = 0.043 and p = 0.010 respectively.

CONCLUSIONS

Although these preliminary results need to be evaluated in a randomized clinical trial, they provide useful infomration about the safety of PRGF and open new perspectives on autologous treatments for joint diseases.

The relationship between HAART use and sexual activity among HIV-positive women of reproductive age in Brazil, South Africa, and Uganda

The purpose of this study was to determine whether current HAART use is associated with recent sexual intercourse among HIV-infected women (18-49 years) from Brazil, South Africa and Uganda. We conducted an analysis of survey data from a cross-sectional study, which enrolled 179 HIV-infected women receiving regular care from the Mbarara Hospital HIV Clinic in Uganda (n=85); the Perinatal HIV Research Unit in Soweto, South Africa (n=50); and the IPEC-Fiocruz cohort in Rio de Janeiro, Brazil (n=44). The primary outcome was sexual intercourse in the previous month. Secondary outcomes were protected sex and contraceptive use. We found that overall, 46% reported recent sexual intercourse. After adjusting for covariates, recent sexual intercourse was not associated with HAART use (AOR: 0.76; 95%CI: 0.34-1.72); however, it was significantly associated with being currently married, wanting to have more children and having higher HAART optimism. Among women reporting recent sexual intercourse (n=83), HAART users were significantly more likely to practice protected sex (crude OR: 3.64; 95%CI: 1.41-9.38) and non-significantly more likely to use contraceptive methods (crude OR: 2.15; 95%CI: 0.77-5.99). In summary, self-reported recent sexual intercourse is not more likely among women on HAART. Moreover, sexually active HAART users may be more likely to practice protected sex and use contraceptives.

Echocardiographic features of cardiac failure in Uganda

Cardiac failure is a common medical presentation in Uganda. This study primarily focuses on the aetiology of heart failure in 65 adult patients and assesses the utility of echocardiography in a resource-limited setting. Our findings suggest that endomyocardial fibrosis is much less prevalent than previously described in other regions of Uganda and highlights the need for more basic descriptive studies on common presenting illnesses in rural Africa.

Differential effect of haloperidol and clozapine on plasma homovanillic acid in elderly schizophrenic patients with or without tardive dyskinesia

BACKGROUND

Plasma homovanillic acid (HVA) changes in response to a challenge of several days with haloperidol have been found to be predictive of the therapeutic response to haloperidol over a longer period of treatment.

METHODS

Twenty-six elderly women who gave informed consent were divided into two groups, with or without tardive dyskinesia, and subjected to an 80-day washout, after which both the dyskinetic and nondyskinetic group was divided, and half of each group given haloperidol or clozapine.

CONCLUSIONS

The nondyskinetic group had a brief rise in plasma HVA, then a decline. The dyskinetic group had no change in plasma HVA. Neither group challenged with clozapine had any change in plasma HVA.

Chronic neuroleptic treatment does not suppress the dynamic characteristics of the dopaminergic receptor D2 system

1. Rats were treated with either haloperidol (0.5 mg/kg) or haloperidol plus an anticholinergic drug (0.5 and 0.15 mg/kg/day respectively) for 3 days, 7 days and 16 months. 2. Estimates made twenty hours after the last doses showed that haloperidol reduced the concentrations of the dopamine metabolites, 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) in the striatum and the olfactory tubercle. 3. A challenge dose of either haloperidol or haloperidol plus an anticholinergic drug was administered to rats pretreated with haloperidol or haloperidol plus an anticholinergic drug; this challenge dose reversed the reduction in dopamine metabolites caused by neuroleptic administration. 4. After sixteen months of haloperidol administration dopamine levels were reduced, but adding an anticholinergic drug to haloperidol treatment prevented this reduction in dopamine concentration.

Persistence of cyclicity of the plasma dopamine metabolite, homovanillic acid, in neuroleptic treated schizophrenic patients

The dopamine metabolite, homovanillic acid, decreases in concentration in plasma between 8:30 A.M. and 12:30 P.M. In patients with schizophrenia this cyclic change is attenuated by chronic neuroleptic treatment; however, if the 8 A.M. dose of neuroleptic is omitted, the decrease in level occurs. Presuming that neuroleptics attenuate the decline through a receptor mediated compensatory increase in dopamine release, it would appear that receptors are not fully occupied by neuroleptics even at therapeutically effective doses. The usual morning decrease in plasma cortisol levels was unaffected by neuroleptics.

Plasma homovanillic acid as a predictor of response to neuroleptics

Fourteen schizophrenic subjects were evaluated for degree of psychosis before and after treatment with the antipsychotic drug haloperidol and for plasma homovanillic acid concentration after four and 28 days of treatment. A significant correlation was found between an increase in homovanillic acid concentration on day 4 or a decrease from day 4 to day 28 and the degree of improvement after four weeks of treatment. Thus, those patients who had the greatest change in plasma homovanillic acid in response to neuroleptic blockade showed the greatest improvement. These and other observations have led us to propose that the central dopaminergic system, through adaptive changes in activity, serves as a physiologic buffer system protecting against destabilization of mental function from diverse biologic or psychologic insults.

Liquid-chromatographic method for determination of homovanillic acid in plasma, with electrochemical detection

We describe a sensitive, simple method for measuring homovanillic acid in human plasma. The method is based on liquid chromatography with electrochemical detection. Sensitivity was 125 pg of homovanillic acid per injection. Samples were deproteinized and extracted with organic solvent before chromatography. Quantification was by the standard-additions technique. Analytical recovery of added HVA was 44.8 (SD 6.2%). We confirmed specificity by using serial amperometric detectors.

Liquid-chromatographic method for determination of homovanillic acid in plasma, with electrochemical detection

We describe a sensitive, simple method for measuring homovanillic acid in human plasma. The method is based on liquid chromatography with electrochemical detection. Sensitivity was 125 pg of homovanillic acid per injection. Samples were deproteinized and extracted with organic solvent before chromatography. Quantification was by the standard-additions technique. Analytical recovery of added HVA was 44.8 (SD 6.2%). We confirmed specificity by using serial amperometric detectors.