Study Selection Summary

A total of twelve studies were included for review: six published qualitative research studies [10, 11, 20,21,22,23]; four written patient testimonial series from a patient advocacy group (Nephcure) [24,25,26,27], and two video patient testimonials from a patient advocacy group (Nephcure) [28, 29]. The 13 studies explored FSGS (n = 7) and NS (n = 6). Six studies included an adult population [11, 21, 22, 24, 25, 28], four studies included a pediatric population [23, 26, 27, 29], and two studies included both adult and adolescent populations [10, 20]. All studies were conducted in the US or Canada. The included studies are summarized in Table S4 in the electronic supplementary material. The process of study selection is documented in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) [30] flow diagram in Fig. 1; no studies were excluded due to quality assessment results.

Fig. 1

Literature review PRISMA flow diagram. No. number

Conceptual Model of the Patient Experience of FSGS

A conceptual model of the patient experience of FSGS is presented in Fig. 2. The conceptual model presents FSGS signs/symptoms, treatment side-effects, and their impact on patients’ functioning and wellbeing. Arrows indicate where there is a posited relationship or interaction between concepts. An existing CM was identified in the published literature [11] and reviewed alongside other evidence. Concepts are organized into related domains and concepts reported by a sub-sample only are noted. Domains and concepts outlined in red are posited to be particularly salient. Some physical experiences were described as a disease sign/symptom and a treatment side effect. Almost all concepts were reported by patients with FSGS; ‘cataracts’ and ‘stunted growth’ were the only concepts reported by patients with NS only.

Fig. 2

Conceptual model of with the patient experience of FSGS/NS. FSGS Focal segmental glomerulosclerosis, NS nephrotic syndrome

ConceptsSigns, Symptoms, Treatment Side-Effects, Direct Impacts of Medical Procedures

The literature documented that FSGS has a relapsing/remitting profile. Patients reported that symptoms were rarely stable across time, describing unpredictable ‘flare-ups’, which caused them both annoyance and concern [10, 11, 20, 24,25,26,27, 29].

Swelling/Puffiness (Edema)

Swelling was the most commonly reported symptom of FSGS, reported by both adult and pediatric patients, and often the symptom that triggered a search for a diagnosis [10, 11, 20, 22, 24,25,26,27,28,29]. Swelling was reported as occurring across all areas of the body, but most frequently in the lower limbs, face/eyes, and stomach/abdomen.

Swelling caused weight gain and skin problems as the skin stretched over the accumulated fluid; in some cases, the skin would break. Swelling was therefore commonly associated with reports of feelings of pain [10, 11, 27, 28], hurt [10, 27], discomfort [10], tightness [11], and pressure due to pressure on the body [10], the stretching of the skin [11, 27, 28], or constriction caused by too-tight clothing, many patients reported difficulty getting dressed and finding appropriate clothing [10].

Swelling could have a significant impact on patients’ appearances and, subsequently, cause emotional discomfort; patients reported feeling embarrassment and self-consciousness when around others, particularly if the swelling was visible in their face, or if it made them appear overweight [10, 26, 28].

Weight Gain/Loss/Redistribution

In addition to the weight gain associated with swelling, changes in weight were attributed as a side effect of corticosteroid treatment [10, 22, 25].

Skin Problems

Skin problems were not solely caused by swelling. Dry/itchy skin was reported in one publication, and named as a particularly bothersome experience that could make it difficult to sleep [11]. It was also reported that corticosteroid treatment could cause skin changes, such as sun sensitivity [29], susceptibility to bruising [11], and darker skin [11].

Respiratory Problems

Patients reported experiencing shortness of breath, typically during daily physical activities such as climbing stairs, and this could induce feelings of panic [10, 11, 22]. Coughing was also reported in two papers, but not in sufficient detail to provide information regarding the type of cough experienced [11, 22].

Sleep Problems

Sleep problems were commonly reported. Most frequently, patients reported difficulty sleeping or difficulty falling asleep, disrupted sleep with frequent awakenings, or sleep that did not make the patient feel restful when they awoke [10, 11, 22, 25, 27]. Difficulty sleeping was commonly associated with corticosteroid treatment, and could be unprovoked or caused by pain or itchy skin. Conversely, patients also reported sleeping ‘too much,’ in association with feelings of fatigue [10, 25].

Urinary Problems

Urinary problems were a key component of FSGS, with patients reporting both reduced urination/an inability to urinate [11, 26, 28], and foamy/bubbly/cloudy urine [11, 22, 25]. Conversely, patients also reported the need to frequently urinate, commonly following the onset of corticosteroid treatment, [11, 22, 24, 28].

Gastrointestinal Problems

Patients reported various gastrointestinal problems [10, 11, 25, 27]. Nausea was often reported as an initial symptom that prompted the search for a diagnosis and also a side effect of treatment [10, 11, 25, 28], and may be associated with vomiting [11, 25, 26, 28]. Nausea and vomiting made it difficult for patients to eat, and to perform some daily activities. Patients also reported stomach bloating, although the literature was unclear whether this was the same or different than the reported abdominal swelling/edema [22, 27], and diarrhea, which was associated with medication [11, 25].

Pains/Aches/Discomfort

Patients often reported experiencing pains [10, 11, 24,25,26,27,28], aches, and discomfort. Pain seemed to be caused by multiple factors. In addition to the pain associated with swelling/edema and skin problems (see previous section), patients reported stomach hurt/pain [24, 27,