Pharmacologic basis for the treatment of tinea capitis

Effect of spray-drying temperature on the formation of flower-like lactose for griseofulvin loading

The effect of spray-drying temperature has been studied for the first time on the formation of flower-like lactose for drug loading in this work. The synthesis of the flower-like lactose involves two steps, namely spray drying and ethanol washing. Four inlet temperatures (140°C, 150°C, 160°C and 200°C) have been used in the spray-drying step. The effect of the spray-drying temperature was significant on the formation of flower-like lactose, in terms of crystallinity, porosity and drug loading capacity. Higher inlet temperatures are more likely to produce lactose in the β form. The engineered flower-like lactose is highly porous, with pores of 1.4, 3.4 and 29.3nm (diameter). Compared with other inlet temperatures, the flower-like lactose dried at 150°C has the lowest degree of crystallinity, the largest pore surface area (38±4m²/g) and pore volume (0.65±0.09cm³/g), and the highest griseofulvin loading capacity (16.2±0.3%, w/w). A griseofulvin dissolution test has suggested that the flower-like lactose can be used as a drug carrier to enhance drug solubility.

Systemic antifungal therapy for tinea capitis in children

BACKGROUND

Tinea capitis is a common contagious fungal infection of the scalp in children. Systemic therapy is required for treatment and to prevent spread. This is an update of the original Cochrane review.

OBJECTIVES

To assess the effects of systemic antifungal drugs for tinea capitis in children.

SEARCH METHODS

We updated our searches of the following databases to November 2015: the Cochrane Skin Group Specialised Register, CENTRAL (2015, Issue 10), MEDLINE (from 1946), EMBASE (from 1974), LILACS (from 1982), and CINAHL (from 1981). We searched five trial registers and checked the reference lists of studies for references to relevant randomised controlled trials (RCTs). We obtained unpublished, ongoing trials and grey literature via correspondence with experts in the field and from pharmaceutical companies.

SELECTION CRITERIA

RCTs of systemic antifungal therapy in children with normal immunity under the age of 18 with tinea capitis confirmed by microscopy, growth of fungi (dermatophytes) in culture or both.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

We included 25 studies (N = 4449); 4 studies (N = 2637) were new to this update.Terbinafine for four weeks and griseofulvin for eight weeks showed similar efficacy for the primary outcome of complete (i.e. clinical and mycological) cure in three studies involving 328 participants with Trichophyton species infections (84.2% versus 79.0%; risk ratio (RR) 1.06, 95% confidence interval (CI) 0.98 to 1.15; low quality evidence).Complete cure with itraconazole (two to six weeks) and griseofulvin (six weeks) was similar in two studies (83.6% versus 91.0%; RR 0.92, 95% CI 0.81 to 1.05; N = 134; very low quality evidence). In two studies, there was no difference between itraconazole and terbinafine for two to three weeks treatment (73.8% versus 78.8%; RR 0.93, 95% CI 0.72 to 1.19; N = 160; low quality evidence). In three studies, there was a similar proportion achieving complete cured with two to four weeks of fluconazole or six weeks of griseofulvin (41.4% versus 52.7%; RR 0.92, 95% CI 0.81 to 1.05; N = 615; moderate quality evidence). Current evidence for ketoconazole versus griseofulvin was limited. One study favoured griseofulvin (12 weeks) because ketoconazole (12 weeks) appeared less effective for complete cure (RR 0.76, 95% CI 0.62 to 0.94; low quality evidence). However, their effects appeared to be similar when the treatment lasted 26 weeks (RR 0.95, 95% CI 0.83 to 1.07; low quality evidence). Another study indicated that complete cure was similar for ketoconazole (12 weeks) and griseofulvin (12 weeks) (RR 0.89, 95% CI 0.57 to 1.39; low quality evidence). For one trial, there was no significant difference for complete cure between fluconazole (for two to three weeks) and terbinafine (for two to three weeks) (82.0% versus 94.0%; RR 0.87, 95% CI 0.75 to 1.01; N = 100; low quality evidence). For complete cure, we did not find a significant difference between fluconazole (for two to three weeks) and itraconazole (for two to three weeks) (82.0% versus 82.0%; RR 1.00, 95% CI 0.83 to 1.20; low quality evidence).This update provides new data: in children with Microsporum infections, a meta-analysis of two studies found that the complete cure was lower for terbinafine (6 weeks) than for griseofulvin (6-12 weeks) (34.7% versus 50.9%; RR 0.68, 95% CI 0.53 to 0.86; N = 334; moderate quality evidence). In the original review, there was no significant difference in complete cure between terbinafine (four weeks) and griseofulvin (eight weeks) in children with Microsporum infections in one small study (27.2% versus 60.0%; RR 0.45, 95% CI 0.15 to 1.35; N = 21; low quality evidence).One study provides new evidence that terbinafine and griseofulvin for six weeks show similar efficacy (49.5% versus 37.8%; RR 1.18, 95% CI 0.74 to 1.88; N = 1006; low quality evidence). However, in children infected with T. tonsurans, terbinafine was better than griseofulvin (52.1% versus 35.4%; RR 1.47, 95% CI 1.22 to 1.77; moderate quality evidence). For children infected with T. violaceum, these two regimens have similar effects (41.3% versus 45.1%; RR 0.91, 95% CI 0.68 to 1.24; low quality evidence). Additionally, three weeks of fluconazole was similar to six weeks of fluconazole in one study in 491 participants infected with T. tonsurans and M. canis (30.2% versus 34.1%; RR 0.88, 95% CI 0.68 to 1.14; low quality evidence).The frequency of adverse events attributed to the study drugs was similar for terbinafine and griseofulvin (9.2% versus 8.3%; RR 1.11, 95% CI 0.79 to 1.57; moderate quality evidence), and severe adverse events were rare (0.6% versus 0.6%; RR 0.97, 95% CI 0.24 to 3.88; moderate quality evidence). Adverse events for terbinafine, griseofulvin, itraconazole, ketoconazole, and fluconazole were all mild and reversible.All of the included studies were at either high or unclear risk of bias in at least one domain. Using GRADE to rate the overall quality of the evidence, lower quality evidence resulted in lower confidence in the estimate of effect.

AUTHORS' CONCLUSIONS

Newer treatments including terbinafine, itraconazole and fluconazole are at least similar to griseofulvin in children with tinea capitis caused by Trichophyton species. Limited evidence suggests that terbinafine, itraconazole and fluconazole have similar effects, whereas ketoconazole may be less effective than griseofulvin in children infected with Trichophyton. With some interventions the proportion achieving complete clinical cure was in excess of 90% (e.g. one study of terbinafine or griseofulvin for Trichophyton infections), but in many of the comparisons tested, the proportion cured was much lower.New evidence from this update suggests that terbinafine is more effective than griseofulvin in children with T. tonsurans infection.However, in children with Microsporum infections, new evidence suggests that the effect of griseofulvin is better than terbinafine. We did not find any evidence to support a difference in terms of adherence between four weeks of terbinafine versus eight weeks of griseofulvin. Not all treatments for tinea capitis are available in paediatric formulations but all have reasonable safety profiles.

Tinea capitis: predictive value of symptoms and time to cure with griseofulvin treatment

OBJECTIVES

To describe (a) the predictive value of symptoms for diagnosis of tinea capitis and (b) the rate and timing of cure with high-dose griseofulvin treatment.

METHODS

This prospective open-label study enrolled children aged 1 to 12 years with clinical tinea capitis. Participants with a positive dermatophyte culture received oral griseofulvin (20-25 mg/kg/day) and topical selenium sulfide shampoo for 6 weeks. Main outcome measures. The rate of symptoms of tinea capitis, and rates of mycologic and clinical cure.

RESULTS

The positive predictive values of any 1, 2, 3, or 4 symptoms for a positive culture were 88%, 82%, 78%, and 77%, respectively. The observed rates of mycologic, clinical, and complete cure were 89%, 66%, and 49%, respectively. conclusion: In a high-risk population it is reasonable to diagnose tinea capitis using one or more cardinal symptoms. Oral griseofulvin at 20 to 25 mg/ kg/day with adjunctive shampooing for 6 weeks is moderately successful as treatment.

Systemic antifungal therapy for tinea capitis in children

BACKGROUND

Tinea capitis is a common contagious fungal infection of the scalp in children. Systemic therapy is required for treatment and to prevent spread.

OBJECTIVES

To assess the effects of systemic anti-fungal drugs for tinea capitis in children.

SEARCH STRATEGY

We searched the Cochrane Skin Group Specialised Register (June 2005), the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 2, 2005), MEDLINE (2003 to June 2005), EMBASE ( 2003 to June 2005), LILACS (1982 to July 2005), CINAHL (1982 to July 2005), the ACP journal club (1991 to July 2005) and Healthstar (1975 to July 2005).

SELECTION CRITERIA

Randomised controlled trials (RCTs) that evaluated systemic antifungal therapy in people with normal immunity under the age of 18 who had tinea capitis confirmed by microscopy or growth of dermatophytes in culture or both.

DATA COLLECTION AND ANALYSIS

At least two authors independently examined each retrieved trial for eligibility and quality.

MAIN RESULTS

We included 21 studies (1812 participants). Infections involving Trichophyton species: Terbinafine for four weeks and griseofulvin for eight weeks showed similar efficacy in 3 studies involving 382 participants (RR 1.09; 95% CI 0.95 to 1.26). Cure rates following treatment with itraconazole and griseofulvin for 6 weeks were similar in 1 study of 35 children (RR 1.06; 95% CI 0.81 to 1.39). Another study of 100 children did not show any significant difference in cure between itraconazole for 2 weeks compared with griseofulvin for 6 weeks (RR 0.89; 95% CI 0.76 to 1.04). There was no difference between itraconazole and terbinafine for treatment periods lasting 2 to 3 weeks in 2 studies involving 160 children (RR 0.93; 95% CI 0.72 to 1.19). Two studies that included 140 children found similar cure rates between 2 to 4 weeks of fluconazole with 6 weeks of griseofulvin (RR 0.92; 95% CI 0.80 to 1.05). Microsporum infections: There was no significant difference in cure between terbinafine and griseofulvin in children with Microsporum infections in 1 small study of 29 children (RR 0.64; 95% CI 0.19 to 2.20).

AUTHORS' CONCLUSIONS

The best evidence suggests that newer treatments including terbinafine, itraconazole and fluconazole may be similar to griseofulvin in children with tinea capitis caused by Trichophyton species. Newer treatments may be preferred because shorter treatment durations may improve treatment adherence, although they may be more expensive. There is not enough evidence on the use of systemic treatments in children with Microsporum infections. Not all treatments for tinea capitis are available in paediatric formulations but all have reasonable safety profiles.

Incidence of Tinea capitis in São Paulo, Brazil

To determine the incidence of tinea capitis in São Paulo, Brazil, an investigation was performed in Private and Public Pediatrics Service involving 4,500 children from 0 to 15 years old during 5 years (1996-2000). Samples were taken from 132 children with suspected fungal infection of the scalp, for direct microscopy and culture. Tinea of scalp was mycologically confirmed in 112 patients (85%). Males were more affected than females in all age groups. Children below 8 years old accounted for more than 75% of the occurrences. Only three cases of tinea capitis were diagnosed in children from 12 to 15 years of age. Tinea capitis was prevalent in 103 cases (91.96%); inflammatory kerion type lesions were diagnosed in 9 patients (8.04%). Microsporum canis (70.5%) and Trichophyton tonsurans (23.2%) were the most common agents followed by T. mentagrophytes (3.6%), M. gypseum (1.8%) and T. rubrum (0.9%).

Pediatric tinea capitis: recognition and management

Tinea capitis (ringworm of the head) is the most common dermatophytosis of childhood with an increasing incidence worldwide. If suspected clinically, further diagnostic procedures, including direct microscopy and culture, should be performed. Other scalp alterations, such as seborrheic dermatitis, atopic eczema, psoriasis, alopecia areata, folliculitis, and pseudopelade, may mimic ringworm of the head and must be identified. A proven fungal infection of scalp skin and hairs warrants immediate initiation of systemic treatment. At present, only oral griseofulvin is approved for therapy of scalp ringworm in children by health authorities. However, the advent of several newer antifungal agents such as itraconazole, fluconazole, and terbinafine has broadened the therapeutic armamentarium in recent years. These agents offer shorter treatment intervals, and their adverse effects and drug interaction profiles appear to be well within acceptable limits. In patients with tinea capitis, systemic therapy at weight-dependent dosages for an appropriate amount of time in conjunction with topical supportive measures will help to prevent disfiguring hair loss, permanent formation of scar tissue, spread of fungal organisms to other cutaneous regions, and infection of other persons.

Tinea capitis: epidemiology, diagnosis and management strategies

Tinea capitis is a common superficial fungal infection of the scalp in children, particularly in those of African descent. Trichophyton tonsuran, an anthropophilic dermatophyte, is responsible for the majority of cases in North America. The clinical presentations are variable and include: (i) a "seborrheic" form that is scaling, often without noticeable hair loss; (ii) a pustular, crusted pattern, either localized or more diffuse; (iii) a "black dot" variety characterized by small black dots within areas of alopecia; (iv) a kerion, which is an inflammatory mass; and (v) a scaly, annular patch. Most experts still consider griseofulvin to be the drug of choice, but recommend a higher dosage of 20-25 mg/kg/day for 8 weeks because of the increase in treatment failures. Despite a history of having an excellent tolerability profile, the long treatment course and higher doses required for griseofulvin have led to consideration of new antifungal agents for this infection. Terbinafine, itraconazole, and fluconazole compartmentalize in skin, hair, and nails, thereby allowing shorter treatment courses of < or =4 weeks. All have generally been shown to be effective in the treatment of tinea capitis and appear relatively well tolerated, with gastrointestinal symptoms being the most common adverse effect. Monitoring for liver enzyme elevations is generally unnecessary if therapy is limited to </=4 weeks. As more data regarding efficacy, tolerability, and dose administration becomes available, one or more of these new antifungal agents may become first-line therapy for tinea capitis. For now, we recommend their use in cases of treatment failure or recurrent noncompliance. Our personal preference in the younger child is fluconazole. It has a favorable tolerability profile and is available in liquid form. In the older child who can take a tablet, terbinafine is recommended. More data is available on this drug in the treatment of tinea capitis than the other two, and it is the least expensive. Although the oral antifungal agents are the most important aspect of therapy, adjunctive therapy may be beneficial. Sporicidal shampoos, such as selenium sulfide, can aid in removing adherent scales and hasten the eradication of viable spores from the scalp in the hope of decreasing the spread of this infection. The use of corticosteroids for the treatment of kerions is controversial. Many of the studies have design flaws or show variable results. We recommend either a short burst of oral corticosteroids or topical corticosteroids in patients with the most severe disease.

Tinea capitis: current concepts

Tinea capitis is an important fungal infection that may at times be a clinical, diagnostic and therapeutic challenge. It is common in childhood around the world, becoming almost epidemic in some communities. The central European and American experience with it is somewhat variable, due to different etiologic fungi. The use of topical antifungal agents and other approaches is stressed as of value alongside the use of systemic antifungal medication.